MMS Csharp app1

README.txt

  AT&T API Samples - MMS app 1
 ------------------------------

This file describes how to set up, configure and run the C# Applications of the AT&T RESTFul sample applications. 
It covers all steps required to register the application on DevConnect and, based on the generated API keys and secrets, 
create and run one's own full-fledged sample applications.

  1. Configuration
  2. Installation
  3. Parameters
  4. Running the application


1. Configuration

  Configuration consists of a few steps necessary to get an application registered on DevConnect with the proper services and 
  endpoints, depending on the type of client-side application (autonomous/non-autonomous). 

  To register an application, go to https://devconnect-api.att.com/ and login with your valid username and password.
  Next, choose "My Apps" from the bar at the top of the page and click the "Setup a New Application" button. 

  Fill in the form, in particular all fields marked as "required".

  Be careful while filling in the "OAuth Redirect URL" field. It should contain the URL that the oAuth provider will redirect
  users to when he/she successfully authenticates and authorizes your application.

NOTE: You MUST select MMS in the list of services under field 'Services' in order to use this sample application code. 

  Having your application registered, you will get back an important pair of data: an API key and Secret key. They are 
  necessary to get your applications working with the AT&T HTML5 APIs. See 'Adjusting parameters' below to learn how to use 
  these keys.

  Initially your newly registered application is restricted to the "Sandbox" environment only. To move it to production,
  you may promote it by clicking the "Promote to production" button. Notice that you will get a different API key and secret,
  so these values in your application should be adjusted accordingly.

  Depending on the kind of authentication used, an application may be based on either the Autonomous Client or the Web-Server 
  Client OAuth flow (see https://devconnect-api.att.com/docs/oauth-v1/client-credentials-grant-type or
  https://devconnect-api.att.com/docs/oauth-v1/authorization-code-grant-type respectively).


2. Installation

** Requirements

   1. To run the this sample application you need an IIS Server. 
   2. Change the value of "href" at the following line in Default.aspx to point to the location of the "common.css" of "style" folder:
	<link rel="stylesheet" type="text/css" href="../../style/common.css"/>
   3. Change the value of the "url" at the following line in common.css to point to the location of the "att.gif" of "images" folder.
	div#header { background:url(../images/att.gif) left center no-repeat; margin: 10px 5px}   To run the this sample application you need an IIS Server. 


3. Parameters

   
Each sample application contains a config.web file. It holds configurable parameters described in an easy to read format. 
Please populate the following parameters in config.web as specified below:

1) api_key                		: {set the value as per your registered application 'API key' field value} 


2) secret_key     	  		 : {set the value as per your registered application 'Secret key' field value} 


3) authorize_redirect_uri 		 : {set the value as per your registered application 'OAuth Redirect URL' field value} 

4) FQDN			  	 : https://api.att.com

5) scope				 : MMS   

6) short_code				: {set the value as per your registered application 'short code' field value}

7) AccessTokenFilePath		: {set the value to the path of the file, which application creates and stores access token }

Note: If your application is promoted from Sandbox environment to Production environment and you decide to use production application settings,
you must update parameters 1-2 as per production application details.



4. Running the application

Suppose you copied the sample app files in your IIS server webroot/mms/app1/ folder, In order to run the sample application, 
type in'http://IIS_HOSTNAME/mms/app1/Default.aspx'

Default.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html xml:lang="en" xmlns="http://www.w3.org/1999/xhtml" lang="en"><head>
	<title>AT&T Sample MMS Application 1 &#8211; Basic MMS Service Application</title>
	<meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"/>
    <link rel="stylesheet" type="text/css" href="../../style/common.css"/>
    <style type="text/css">
        .style1
        {
            font-style: normal;
            font-variant: normal;
            font-weight: bold;
            font-size: 12px;
            line-height: normal;
            font-family: Arial, Sans-serif;
            width: 92px;
        }
    </style>
    </head>
<body>
<div id="container">
<!-- open HEADER --><div id="header">
<div>
    <div id="hcLeft">Server Time:</div>
       	<div id="hcRight">
            <asp:Label ID="serverTimeLabel" runat="server" Text="Label"></asp:Label>
        </div>
    </div>
<div>
    <div id="hcLeft">Client Time:</div>
	<div id="hcRight">
        <script language="JavaScript" type="text/javascript">
            var myDate = new Date();
            document.write(myDate);
        </script>
    </div>
</div>
<div>
    <div id="hcLeft">User Agent:</div>    
	<div id="hcRight">
        <script language="JavaScript" type="text/javascript">
            document.write("" + navigator.userAgent);
        </script>
    </div>
</div>

<br clear="all" />
</div><!-- close HEADER -->

<div id="wrapper">
<div id="content">

<h1>AT&T Sample MMS Application 1 � Basic MMS Service Application</h1>
<h2>Feature 1: Send MMS Message</h2>

</div>
</div>

<br clear="all" />
<form id="form1" runat="server">           
<div id="navigation">

<table border="0" width="100%">
  <tbody>
  <tr>
    <td width="20%" valign="top" class="label">Phone:</td>
    <td class="cell">
        <asp:TextBox ID="phoneTextBox" runat="server" Width="199px" MaxLength="16"></asp:TextBox>     
            </td>
  </tr> 
  <tr>
    <td valign="top" class="label">Message:</td>
    <td class="cell">
        <asp:TextBox ID="messageTextBox" runat="server" Height="99px" 
            TextMode="MultiLine" Width="291px"></asp:TextBox></td>
  </tr>
  </tbody>
</table>

</div>

<div id="extraleft">
<div class="warning" >
<strong>WARNING:</strong><br />
total size of all attachments cannot exceed 600 KB.
</div>
</div>
<div id="extra">
<table border="0" width="100%">
  <tbody>
  <tr>
    <td valign="bottom" class="style1">Attachment 1:</td>
    <td class="cell"><asp:FileUpload ID="FileUpload1" runat="server"/>
    </td>
  </tr>
  <tr>
    <td valign="bottom" class="style1">Attachment 2:</td>
    <td class="cell"><asp:FileUpload ID="FileUpload2" runat="server"/>
    </td>
  </tr>
  <tr>
    <td valign="bottom" class="style1">Attachment 3:</td>
    <td class="cell"><asp:FileUpload ID="FileUpload3" runat="server"/>
    </td>
  </tr>
  </tbody></table>
  <table>
  <tbody>
  <tr>
  	<td>
          <asp:Button ID="sendMMSMessageButton" runat="server" Text="Send MMS Message" 
              onclick="sendMMSMessageButton_Click" /></td>
  </tr>
  </tbody></table>
</div>
<br clear="all" />
<div align="center">
    <asp:Panel ID="sendMessagePanel" runat="server" Font-Names="Calibri"  Font-Size="XX-Small">
    </asp:Panel></div>
<br clear="all" />

<div id="wrapper">
<div id="content">

<h2><br />
Feature 2: Get Delivery Status</h2>

</div>
</div>
<div id="navigation">

<table border="0" width="100%">
  <tbody>
  <tr>
    <td width="20%" valign="top" class="label">Message ID:</td>
    <td class="cell">
        <asp:TextBox ID="messageIDTextBox" runat="server" Width="233px"></asp:TextBox>
    </td>
  </tr>
  </tbody></table>
  
</div>
<div id="extra">

<table border="0" width="100%">
  <tbody>
  <tr>
    <td class="cell">
        <asp:Button ID="getStatusButton" runat="server" Text="GetStatus" 
            onclick="getStatusButton_Click" />
    </td>
  </tr>
  </tbody></table>

</div>
<br clear="all" />
<div align="center">
    <asp:Panel ID="getStatusPanel" runat="server" Font-Names="Calibri" Font-Size="XX-Small">
    </asp:Panel>
</div>
<br clear="all" />




<div id="footer">

	<div style="float: right; width: 20%; font-size: 9px; text-align: right">Powered by AT&amp;T Virtual Mobile</div>
    <p>� 2011 AT&amp;T Intellectual Property. All rights reserved.  <a href="http://developer.att.com/" target="_blank">http://developer.att.com</a>
<br>
The Application hosted on this site are working examples intended to be used for reference in creating products to consume AT&amp;T Services and  not meant to be used as part of your product.  The data in these pages is for test purposes only and intended only for use as a reference in how the services perform.
<br>
For download of tools and documentation, please go to <a href="https://devconnect-api.att.com/" target="_blank">https://devconnect-api.att.com</a>
<br>
For more information contact <a href="mailto:[email protected]">[email protected]</a>

</div>
</form>

</body></html>

Default.aspx.cs

//Licensed by AT&T under 'Software Development Kit Tools Agreement.' September 2011
//TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION: http://developer.att.com/sdk_agreement/
//Copyright 2011 AT&T Intellectual Property. All rights reserved. http://developer.att.com
//For more information contact [email protected]

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Net;
using System.IO;
using System.Web.Services;
using System.Text;
using System.Configuration;
using System.Web.Script.Serialization;
using System.Drawing;
using System.Net;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;

public partial class Default : System.Web.UI.Page
{
    string shortCode, FQDN, accessTokenFilePath, oauthFlow;
    string api_key, secret_key, auth_code, access_token, authorize_redirect_uri, scope, expiryMilliSeconds, refresh_token, lastTokenTakenTime, refreshTokenExpiryTime;

    /* This function reads the Access Token File and stores the values of access token, expiry seconds
     * refresh token, last access token time and refresh token expiry time
     * This funciton returns true, if access token file and all others attributes read successfully otherwise returns false
     */
    public bool readAccessTokenFile()
    {
        try
        {
            FileStream file = new FileStream(Request.MapPath(accessTokenFilePath), FileMode.OpenOrCreate, FileAccess.Read);
            StreamReader sr = new StreamReader(file);
            access_token = sr.ReadLine();
            expiryMilliSeconds = sr.ReadLine();
            refresh_token = sr.ReadLine();
            lastTokenTakenTime = sr.ReadLine();
            refreshTokenExpiryTime = sr.ReadLine();
            sr.Close();
            file.Close();
        }
        catch (Exception ex)
        {
            return false;
        }
        if ((access_token == null) || (expiryMilliSeconds == null) || (refresh_token == null) || (lastTokenTakenTime == null) || (refreshTokenExpiryTime == null))
        {
            return false;
        }
        return true;
    }

    /* This function validates the expiry of the access token and refresh token,
     * function compares the current time with the refresh token taken time, if current time is greater then 
     * returns INVALID_REFRESH_TOKEN
     * function compares the difference of last access token taken time and the current time with the expiry seconds, if its more,
     * funciton returns INVALID_ACCESS_TOKEN
     * otherwise returns VALID_ACCESS_TOKEN
    */
    public string isTokenValid()
    {
        try
        {

            DateTime currentServerTime = DateTime.UtcNow.ToLocalTime();
            DateTime lastRefreshTokenTime = DateTime.Parse(refreshTokenExpiryTime);
            TimeSpan refreshSpan = currentServerTime.Subtract(lastRefreshTokenTime);
            if (currentServerTime >= lastRefreshTokenTime)
            {
                return "INVALID_ACCESS_TOKEN";
            }
            DateTime lastTokenTime = DateTime.Parse(lastTokenTakenTime);
            TimeSpan tokenSpan = currentServerTime.Subtract(lastTokenTime);
            if (((tokenSpan.TotalSeconds)) > Convert.ToInt32(expiryMilliSeconds))
            {
                return "REFRESH_ACCESS_TOKEN";
            }
            else
            {
                return "VALID_ACCESS_TOKEN";
            }
        }
        catch (Exception ex)
        {
            return "INVALID_ACCESS_TOKEN";
        }
    }


    /* This function get the access token based on the type parameter type values.
     * If type value is 1, access token is fetch for client credential flow
     * If type value is 2, access token is fetch for client credential flow based on the exisiting refresh token
     */
    public bool getAccessToken(int type, Panel panelParam)
    {
        /*  This is client credential flow: */
        if (type == 1)
        {
            try
            {
                DateTime currentServerTime = DateTime.UtcNow.ToLocalTime();
                WebRequest accessTokenRequest = System.Net.HttpWebRequest.Create("" + FQDN + "/oauth/token");
                accessTokenRequest.Method = "POST";
                string oauthParameters = "client_id=" + api_key.ToString() + "&client_secret=" + secret_key.ToString() + "&grant_type=client_credentials&scope=MMS";
                accessTokenRequest.ContentType = "application/x-www-form-urlencoded";
                //sendSmsRequestObject.Accept = "application/json";
                UTF8Encoding encoding = new UTF8Encoding();
                byte[] postBytes = encoding.GetBytes(oauthParameters);
                accessTokenRequest.ContentLength = postBytes.Length;
                Stream postStream = accessTokenRequest.GetRequestStream();
                postStream.Write(postBytes, 0, postBytes.Length);
                postStream.Close();
                WebResponse accessTokenResponse = accessTokenRequest.GetResponse();
                using (StreamReader accessTokenResponseStream = new StreamReader(accessTokenResponse.GetResponseStream()))
                {
                    string jsonAccessToken = accessTokenResponseStream.ReadToEnd().ToString();
                    JavaScriptSerializer deserializeJsonObject = new JavaScriptSerializer();
                    AccessTokenResponse deserializedJsonObj = (AccessTokenResponse)deserializeJsonObject.Deserialize(jsonAccessToken, typeof(AccessTokenResponse));
                    access_token = deserializedJsonObj.access_token.ToString();
                    expiryMilliSeconds = deserializedJsonObj.expires_in.ToString();
                    refresh_token = deserializedJsonObj.refresh_token.ToString();
                    FileStream file = new FileStream(Request.MapPath(accessTokenFilePath), FileMode.OpenOrCreate, FileAccess.Write);
                    StreamWriter sw = new StreamWriter(file);
                    sw.WriteLine(access_token);
                    sw.WriteLine(expiryMilliSeconds);
                    sw.WriteLine(refresh_token);
                    sw.WriteLine(currentServerTime.ToLongDateString() + " " + currentServerTime.ToLongTimeString());
                    lastTokenTakenTime = currentServerTime.ToLongDateString() + " " + currentServerTime.ToLongTimeString();
                    //Refresh token valids for 24 hours
                    DateTime refreshExpiry = currentServerTime.AddHours(24);
                    refreshTokenExpiryTime = refreshExpiry.ToLongDateString() + " " + refreshExpiry.ToLongTimeString();
                    sw.WriteLine(refreshExpiry.ToLongDateString() + " " + refreshExpiry.ToLongTimeString());
                    sw.Close();
                    file.Close();
                    // Close and clean up the StreamReader
                    accessTokenResponseStream.Close();
                    return true;
                }
            }
            catch (Exception ex)
            {
                drawPanelForFailure(panelParam, ex.ToString());
                return false;
            }
        }
        else if (type == 2)
        {
            try
            {
                DateTime currentServerTime = DateTime.UtcNow.ToLocalTime();
                WebRequest accessTokenRequest = System.Net.HttpWebRequest.Create("" + FQDN + "/oauth/token");
                accessTokenRequest.Method = "POST";
                string oauthParameters = "grant_type=refresh_token&client_id=" + api_key.ToString() + "&client_secret=" + secret_key.ToString() + "&refresh_token=" + refresh_token.ToString();
                accessTokenRequest.ContentType = "application/x-www-form-urlencoded";
                //sendSmsRequestObject.Accept = "application/json";
                UTF8Encoding encoding = new UTF8Encoding();
                byte[] postBytes = encoding.GetBytes(oauthParameters);
                accessTokenRequest.ContentLength = postBytes.Length;
                Stream postStream = accessTokenRequest.GetRequestStream();
                postStream.Write(postBytes, 0, postBytes.Length);
                postStream.Close();
                WebResponse accessTokenResponse = accessTokenRequest.GetResponse();
                using (StreamReader accessTokenResponseStream = new StreamReader(accessTokenResponse.GetResponseStream()))
                {
                    string access_token_json = accessTokenResponseStream.ReadToEnd().ToString();
                    JavaScriptSerializer deserializeJsonObject = new JavaScriptSerializer();
                    AccessTokenResponse deserializedJsonObj = (AccessTokenResponse)deserializeJsonObject.Deserialize(access_token_json, typeof(AccessTokenResponse));
                    access_token = deserializedJsonObj.access_token.ToString();
                    expiryMilliSeconds = deserializedJsonObj.expires_in.ToString();
                    refresh_token = deserializedJsonObj.refresh_token.ToString();
                    FileStream file = new FileStream(Request.MapPath(accessTokenFilePath), FileMode.OpenOrCreate, FileAccess.Write);
                    StreamWriter sw = new StreamWriter(file);
                    sw.WriteLine(access_token);
                    sw.WriteLine(expiryMilliSeconds);
                    sw.WriteLine(refresh_token);
                    sw.WriteLine(currentServerTime.ToLongDateString() + " " + currentServerTime.ToLongTimeString());
                    lastTokenTakenTime = currentServerTime.ToLongDateString() + " " + currentServerTime.ToLongTimeString();
                    //Refresh token valids for 24 hours
                    DateTime refreshExpiry = currentServerTime.AddHours(24);
                    refreshTokenExpiryTime = refreshExpiry.ToLongDateString() + " " + refreshExpiry.ToLongTimeString();
                    sw.WriteLine(refreshExpiry.ToLongDateString() + " " + refreshExpiry.ToLongTimeString());
                    sw.Close();
                    file.Close();
                    accessTokenResponseStream.Close();
                    return true;
                }
            }
            catch (Exception ex)
            {
                drawPanelForFailure(panelParam, ex.ToString());
                return false;
            }
        }
        return false;
    }

    /* This function is used to neglect the ssl handshake error with authentication server */

    public static void BypassCertificateError()
    {
        ServicePointManager.ServerCertificateValidationCallback +=
            delegate(Object sender1, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
            {
                return true;
            };
    }
    /* This function is used to read access token file and validate the access token
     * this function returns true if access token is valid, or else false is returned
     */
    public bool readAndGetAccessToken(Panel panelParam)
    {
        bool result = true;
        if (readAccessTokenFile() == false)
        {
            result = getAccessToken(1, panelParam);
        }
        else
        {
            string tokenValidity = isTokenValid();
            if (tokenValidity.CompareTo("REFRESH_ACCESS_TOKEN") == 0)
            {
                result = getAccessToken(2, panelParam);
            }
            else if (string.Compare(isTokenValid(), "INVALID_ACCESS_TOKEN") == 0)
            {
                result = getAccessToken(1, panelParam);
            }
        }
        return result;
    }
    /*
     * This function is called when the applicaiton page is loaded into the browser.
     * This fucntion reads the web.config and gets the values of the attributes
     * 
     */
    protected void Page_Load(object sender, EventArgs e)
    {
        try
        {
            BypassCertificateError();
            DateTime currentServerTime = DateTime.UtcNow;
            serverTimeLabel.Text = String.Format("{0:ddd, MMM dd, yyyy HH:mm:ss}", currentServerTime) + " UTC";
            if (ConfigurationManager.AppSettings["AccessTokenFilePath"] != null)
            {
                accessTokenFilePath = ConfigurationManager.AppSettings["AccessTokenFilePath"];
            }
            else
            {
                accessTokenFilePath = "~\\MMSApp1AccessToken.txt";
            }
            if (ConfigurationManager.AppSettings["FQDN"] == null)
            {
                drawPanelForFailure(sendMessagePanel, "FQDN is not defined in configuration file");
                return;
            }
            FQDN = ConfigurationManager.AppSettings["FQDN"].ToString();
            if (ConfigurationManager.AppSettings["short_code"] == null)
            {
                drawPanelForFailure(sendMessagePanel, "short_code is not defined in configuration file");
                return;
            }
            shortCode = ConfigurationManager.AppSettings["short_code"].ToString();
            if (ConfigurationManager.AppSettings["api_key"] == null)
            {
                drawPanelForFailure(sendMessagePanel, "api_key is not defined in configuration file");
                return;
            }
            api_key = ConfigurationManager.AppSettings["api_key"].ToString();
            if (ConfigurationManager.AppSettings["secret_key"] == null)
            {
                drawPanelForFailure(sendMessagePanel, "secret_key is not defined in configuration file");
                return;
            }
            secret_key = ConfigurationManager.AppSettings["secret_key"].ToString();
            if (ConfigurationManager.AppSettings["scope"] == null)
            {
                scope = "MMS";
            }
            else
            {
                scope = ConfigurationManager.AppSettings["scope"].ToString();
            }
        }
        catch (Exception ex)
        {
            drawPanelForFailure(sendMessagePanel, ex.ToString());
            Response.Write(ex.ToString());
        }
    }
    /*
 * This funciton calls send mms message to send the selected files
 */
    private void sendMms()
    {
        try
        {
            string smsAddressInput = phoneTextBox.Text.ToString();
            string smsAddressFormatted;
            string phoneStringPattern = "^\\d{3}-\\d{3}-\\d{4}$";
            if (System.Text.RegularExpressions.Regex.IsMatch(smsAddressInput, phoneStringPattern))
            {
                smsAddressFormatted = smsAddressInput.Replace("-", "");
            }
            else
            {
                smsAddressFormatted = smsAddressInput;
            }
            string smsAddressForRequest = smsAddressFormatted.ToString();
            long tryParseResult = 0;
            if (smsAddressFormatted.Length == 16 && smsAddressFormatted.StartsWith("tel:+1"))
            {
                smsAddressFormatted = smsAddressFormatted.Substring(6, 10);
            }
            else if (smsAddressFormatted.Length == 15 && smsAddressFormatted.StartsWith("tel:+"))
            {
                smsAddressFormatted = smsAddressFormatted.Substring(5, 10);
            }
            else if (smsAddressFormatted.Length == 14 && smsAddressFormatted.StartsWith("tel:"))
            {
                smsAddressFormatted = smsAddressFormatted.Substring(4, 10);
            }
            else if (smsAddressFormatted.Length == 12 && smsAddressFormatted.StartsWith("+1"))
            {
                smsAddressFormatted = smsAddressFormatted.Substring(2, 10);
            }
            else if (smsAddressFormatted.Length == 11 && smsAddressFormatted.StartsWith("1"))
            {
                smsAddressFormatted = smsAddressFormatted.Substring(1, 10);
            }
            if ((smsAddressFormatted.Length != 10) || (!long.TryParse(smsAddressFormatted, out tryParseResult)))
            {
                drawPanelForFailure(sendMessagePanel, "Invalid phone number: " + smsAddressInput);
            }
            else
            {
                string mmsAddress = smsAddressForRequest.ToString();
                string mmsMessage = messageTextBox.Text.ToString();

                if (mmsMessage == null || mmsMessage.Length <=0)
                {
                    drawPanelForFailure(sendMessagePanel, "Message is null or empty");
                    return;
                }

                if ((Session["mmsFilePath1"] == null) && (Session["mmsFilePath2"] == null) && (Session["mmsFilePath3"] == null))
                {
                    string boundaryToSend = "----------------------------" + DateTime.Now.Ticks.ToString("x");
                    HttpWebRequest mmsRequestObject1 = (HttpWebRequest)WebRequest.Create("" + FQDN + "/rest/mms/2/messaging/outbox?access_token=" + access_token.ToString());
                    mmsRequestObject1.ContentType = "multipart/form-data; type=\"application/x-www-form-urlencoded\"; start=\"<startpart>\"; boundary=\"" + boundaryToSend + "\"\r\n";
                    mmsRequestObject1.Method = "POST";
                    mmsRequestObject1.KeepAlive = true;
                    UTF8Encoding encoding1 = new UTF8Encoding();
                    byte[] bytesToSend = encoding1.GetBytes("");
                    string mmsParameters = "Address=" + Server.UrlEncode("tel:" + mmsAddress) + "&Subject=" + Server.UrlEncode(mmsMessage);
                    string dataToSend = "";
                    dataToSend += "--" + boundaryToSend + "\r\n";
                    dataToSend += "Content-Type: application/x-www-form-urlencoded; charset=UTF-8\r\nContent-Transfer-Encoding: 8bit\r\nContent-Disposition: form-data; name=\"root-fields\"\r\nContent-ID: <startpart>\r\n\r\n"+ mmsParameters +"\r\n";
                    dataToSend += "--" + boundaryToSend + "--\r\n";
                    bytesToSend = encoding1.GetBytes(dataToSend);
                    int sizeToSend = bytesToSend.Length;
                    var memBufToSend = new MemoryStream(new byte[sizeToSend], 0, sizeToSend, true, true);
                    memBufToSend.Write(bytesToSend, 0, bytesToSend.Length);
                    //ms.Write(image, 0, image.Length);
                    byte[] finalData = memBufToSend.GetBuffer();
                    mmsRequestObject1.ContentLength = finalData.Length;
                    Stream postStream1 = mmsRequestObject1.GetRequestStream();
                    postStream1.Write(finalData, 0, finalData.Length);
                    postStream1.Close();

                    WebResponse mmsResponseObject1 = mmsRequestObject1.GetResponse();
                    using (StreamReader sr = new StreamReader(mmsResponseObject1.GetResponseStream()))
                    {
                        string mmsResponseData = sr.ReadToEnd();
                        JavaScriptSerializer deserializeJsonObject = new JavaScriptSerializer();
                        mmsResponseId deserializedJsonObj = (mmsResponseId)deserializeJsonObject.Deserialize(mmsResponseData, typeof(mmsResponseId));
                        messageIDTextBox.Text = deserializedJsonObj.id.ToString();
                        drawPanelForSuccess(sendMessagePanel, deserializedJsonObj.id.ToString());
                        sr.Close();
                    }
                    return;

                }
               
                string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x");

                HttpWebRequest mmsRequestObject = (HttpWebRequest)WebRequest.Create("" + FQDN + "/rest/mms/2/messaging/outbox?access_token=" + access_token.ToString());
                mmsRequestObject.ContentType = "multipart/form-data; type=\"application/x-www-form-urlencoded\"; start=\"<startpart>\"; boundary=\"" + boundary + "\"\r\n";
                mmsRequestObject.Method = "POST";
                mmsRequestObject.KeepAlive = true;
                UTF8Encoding encoding = new UTF8Encoding();
                byte[] postBytes = encoding.GetBytes("");
                byte[] postBytes1 = encoding.GetBytes("");
                byte[] postBytes2 = encoding.GetBytes("");
                byte[] totalpostBytes = encoding.GetBytes("");
                string sendMMSData = "Address=" + Server.UrlEncode("tel:" + mmsAddress) + "&Subject=" + Server.UrlEncode(mmsMessage);
                string data = "";
                data += "--" + boundary + "\r\n";
                data += "Content-Type:application/x-www-form-urlencoded;charset=UTF-8\r\nContent-Transfer-Encoding:8bit\r\nContent-ID:<startpart>\r\n\r\n" + sendMMSData + "\r\n";

                if (Session["mmsFilePath1"] != null)
                {
                    string mmsFileName = Path.GetFileName(Session["mmsFilePath1"].ToString());
                    FileStream fs = new FileStream(Session["mmsFilePath1"].ToString(), FileMode.Open, FileAccess.Read);
                    BinaryReader br = new BinaryReader(fs);
                    byte[] image = br.ReadBytes((int)fs.Length);
                    br.Close();
                    fs.Close();
                    data += "--" + boundary + "\r\n";
                    data += "Content-Disposition:attachment;name=\"" + mmsFileName + "\"\r\n";
                    data += "Content-Type:image/gif\r\n";
                    data += "Content-ID:<" + mmsFileName + ">\r\n";
                    data += "Content-Transfer-Encoding:binary\r\n\r\n";
                    byte[] firstPart = encoding.GetBytes(data);
                    int newSize = firstPart.Length + image.Length;
                    var ms = new MemoryStream(new byte[newSize], 0, newSize, true, true);
                    ms.Write(firstPart, 0, firstPart.Length);
                    ms.Write(image, 0, image.Length);
                    postBytes = ms.GetBuffer();
                    totalpostBytes = postBytes;
                    //Session["mmsFilePath1"] = null;
                }

                if (Session["mmsFilePath2"] != null)
                {
                    if (Session["mmsFilePath1"] != null)
                        data = "--" + boundary + "\r\n";
                    else
                        data += "--" + boundary + "\r\n";
                    string mmsFileName = Path.GetFileName(Session["mmsFilePath2"].ToString());
                    FileStream fs = new FileStream(Session["mmsFilePath2"].ToString(), FileMode.Open, FileAccess.Read);
                    BinaryReader br = new BinaryReader(fs);
                    byte[] image = br.ReadBytes((int)fs.Length);
                    br.Close();
                    fs.Close();
                    data += "Content-Disposition:attachment;name=\"" + mmsFileName + "\"\r\n";
                    data += "Content-Type:image/gif\r\n";
                    data += "Content-ID:<" + mmsFileName + ">\r\n";
                    data += "Content-Transfer-Encoding:binary\r\n\r\n";
                    byte[] firstPart = encoding.GetBytes(data);
                    int newSize = firstPart.Length + image.Length;
                    var ms = new MemoryStream(new byte[newSize], 0, newSize, true, true);
                    ms.Write(firstPart, 0, firstPart.Length);
                    ms.Write(image, 0, image.Length);
                    postBytes1 = ms.GetBuffer();
                    //byte[] secondpart = ms.GetBuffer();
                    //byte[] thirdpart = encoding.GetBytes("\r\n--" + boundary + "--\r\n");
                    if (Session["mmsFilePath1"] != null)
                    {
                        var ms2 = JoinTwoByteArrays(postBytes, postBytes1);
                        totalpostBytes = ms2.GetBuffer();
                    }
                    else
                    {
                        totalpostBytes = postBytes1;
                    }
                    //Session["mmsFilePath2"] = null;
                }

                if (Session["mmsFilePath3"] != null)
                {
                    if (Session["mmsFilePath1"] != null || Session["mmsFilePath2"] != null)
                        data = "--" + boundary + "\r\n";
                    else
                        data += "--" + boundary + "\r\n";
                    string mmsFileName = Path.GetFileName(Session["mmsFilePath3"].ToString());
                    FileStream fs = new FileStream(Session["mmsFilePath3"].ToString(), FileMode.Open, FileAccess.Read);
                    BinaryReader br = new BinaryReader(fs);
                    byte[] image = br.ReadBytes((int)fs.Length);
                    br.Close();
                    fs.Close();
                    data += "Content-Disposition:attachment;name=\"" + mmsFileName + "\"\r\n";
                    data += "Content-Type:image/gif\r\n";
                    data += "Content-ID:<" + mmsFileName + ">\r\n";
                    data += "Content-Transfer-Encoding:binary\r\n\r\n";
                    byte[] firstPart = encoding.GetBytes(data);
                    int newSize = firstPart.Length + image.Length;
                    var ms = new MemoryStream(new byte[newSize], 0, newSize, true, true);
                    ms.Write(firstPart, 0, firstPart.Length);
                    ms.Write(image, 0, image.Length);
                    postBytes2 = ms.GetBuffer();
                    if (Session["mmsFilePath1"] != null || Session["mmsFilePath2"] != null)
                    {
                        byte[] temp = totalpostBytes;
                        var ms2 = JoinTwoByteArrays(temp, postBytes2);
                        totalpostBytes = ms2.GetBuffer();
                    }
                    else
                    {
                        totalpostBytes = postBytes2;
                    }
                }

                byte[] byteLastBoundary = encoding.GetBytes("\r\n--" + boundary + "--\r\n");
                //int totalSize = postBytes.Length + postBytes1.Length + postBytes2.Length + byteLastBoundary.Length;
                int totalSize = totalpostBytes.Length + byteLastBoundary.Length;
                var totalMS = new MemoryStream(new byte[totalSize], 0, totalSize, true, true);
                totalMS.Write(totalpostBytes, 0, totalpostBytes.Length);
                totalMS.Write(byteLastBoundary, 0, byteLastBoundary.Length);
                byte[] finalpostBytes = totalMS.GetBuffer();
                mmsRequestObject.ContentLength = finalpostBytes.Length;
                Stream postStream = mmsRequestObject.GetRequestStream();
                postStream.Write(finalpostBytes, 0, finalpostBytes.Length);
                postStream.Close();

                WebResponse mmsResponseObject = mmsRequestObject.GetResponse();
                using (StreamReader sr = new StreamReader(mmsResponseObject.GetResponseStream()))
                {
                    string mmsResponseData = sr.ReadToEnd();
                    JavaScriptSerializer deserializeJsonObject = new JavaScriptSerializer();
                    mmsResponseId deserializedJsonObj = (mmsResponseId)deserializeJsonObject.Deserialize(mmsResponseData, typeof(mmsResponseId));
                    messageIDTextBox.Text = deserializedJsonObj.id.ToString();
                    drawPanelForSuccess(sendMessagePanel, deserializedJsonObj.id.ToString());
                    sr.Close();
                }
                mmsRequestObject = null;
                int indexj = 1;
                while (indexj <= 3)
                {
                    if (Convert.ToString(Session["mmsFilePath" + indexj]) != "")
                    {
                        if (File.Exists(Session["mmsFilePath" + indexj].ToString()))
                        {
                            System.IO.FileInfo fileInfo = new System.IO.FileInfo(Session["mmsFilePath" + indexj].ToString());
                            fileInfo.Delete();
                            Session["mmsFilePath" + indexj] = null;
                        }
                    }
                    indexj++;
                }
            }
        }
        catch (Exception ex)
        {
            drawPanelForFailure(sendMessagePanel, ex.ToString());
            int index = 1;

            while (index <= 3)
            {
                if (Convert.ToString(Session["mmsFilePath" + index]) != "")
                {
                    if (File.Exists(Session["mmsFilePath" + index].ToString()))
                    {
                        System.IO.FileInfo fileInfo = new System.IO.FileInfo(Session["mmsFilePath" + index].ToString());
                        fileInfo.Delete();
                        Session["mmsFilePath" + index] = null;
                    }
                }
                index++;
            }
        }
    }
    /* this function add two byte arrays and returns the address of buffer */
    private static MemoryStream JoinTwoByteArrays(byte[] firstByteArray, byte[] secondByteArray)
    {
        int newSize = firstByteArray.Length + secondByteArray.Length;
        var ms = new MemoryStream(new byte[newSize], 0, newSize, true, true);
        ms.Write(firstByteArray, 0, firstByteArray.Length);
        ms.Write(secondByteArray, 0, secondByteArray.Length);
        return ms;
    }

    /* this function draws success table */
    private void drawPanelForSuccess(Panel panelParam, string message)
    {
        Table table = new Table();
        table.Font.Name = "Sans-serif";
        table.Font.Size = 9;
        table.BorderStyle = BorderStyle.Outset;
        table.Width = Unit.Pixel(650);
        TableRow rowOne = new TableRow();
        TableCell rowOneCellOne = new TableCell();
        rowOneCellOne.Font.Bold = true;
        rowOneCellOne.Text = "SUCCESS:";
        // rowOneCellOne.BorderWidth = 1;
        rowOne.Controls.Add(rowOneCellOne);
        table.Controls.Add(rowOne);
        TableRow rowTwo = new TableRow();
        TableCell rowTwoCellOne = new TableCell();
        rowTwoCellOne.Font.Bold = true;
        rowTwoCellOne.Text = "Message ID:";
        rowTwoCellOne.Width = Unit.Pixel(70);
        //rowOneCellOne.BorderWidth = 1;
        rowTwo.Controls.Add(rowTwoCellOne);
        TableCell rowTwoCellTwo = new TableCell();
        rowTwoCellTwo.Text = message.ToString();
        //rowTwoCellOne.BorderWidth = 1;
        rowTwo.Controls.Add(rowTwoCellTwo);
        table.Controls.Add(rowTwo);
        table.BorderWidth = 2;
        table.BorderColor = Color.DarkGreen;
        table.BackColor = System.Drawing.ColorTranslator.FromHtml("#cfc");
        panelParam.Controls.Add(table);
    }
    /* this function draws error table */
    private void drawPanelForFailure(Panel panelParam, string message)
    {
        Table table = new Table();
        table.Font.Name = "Sans-serif";
        table.Font.Size = 9;
        table.BorderStyle = BorderStyle.Outset;
        table.Width = Unit.Pixel(650);
        TableRow rowOne = new TableRow();
        TableCell rowOneCellOne = new TableCell();
        rowOneCellOne.Font.Bold = true;
        rowOneCellOne.Text = "ERROR:";
        rowOne.Controls.Add(rowOneCellOne);
        //rowOneCellOne.BorderWidth = 1;
        table.Controls.Add(rowOne);
        TableRow rowTwo = new TableRow();
        TableCell rowTwoCellOne = new TableCell();
        //rowTwoCellOne.BorderWidth = 1;
        rowTwoCellOne.Text = message.ToString();
        rowTwo.Controls.Add(rowTwoCellOne);
        table.Controls.Add(rowTwo);
        table.BorderWidth = 2;
        table.BorderColor = Color.Red;
        table.BackColor = System.Drawing.ColorTranslator.FromHtml("#fcc");
        panelParam.Controls.Add(table);
    }

    /* this funciton is called when user clicks on send mms button */

    protected void sendMMSMessageButton_Click(object sender, EventArgs e)
    {
        try
        {
            if (readAndGetAccessToken(sendMessagePanel) == true)
            {
                if (access_token == null || access_token.Length <= 0)
                {
                    //drawPanelForFailure(sendSMSPanel, "Invalid access token");
                    return;
                }
                long fileSize = 0;
                if (FileUpload1.FileName.ToString() != "")
                {
                    FileUpload1.SaveAs(Request.MapPath(FileUpload1.FileName.ToString()));
                    Session["mmsFilePath1"] = Request.MapPath(FileUpload1.FileName);
                    FileInfo fileInfoObj = new FileInfo(Session["mmsFilePath1"].ToString());
                    fileSize = fileSize + fileInfoObj.Length / 1024;
                    if (fileSize > 600)
                    {
                        drawPanelForFailure(sendMessagePanel, "Attachment file size exceeded 600kb");
                        return;
                    }
                }
                if (FileUpload2.FileName.ToString() != "")
                {
                    FileUpload2.SaveAs(Request.MapPath(FileUpload2.FileName));
                    Session["mmsFilePath2"] = Request.MapPath(FileUpload2.FileName);
                    FileInfo fileInfoObj = new FileInfo(Session["mmsFilePath2"].ToString());
                    fileSize = fileSize + fileInfoObj.Length / 1024;
                    if (fileSize > 600)
                    {
                        drawPanelForFailure(sendMessagePanel, "Attachment file size exceeded 600kb");
                        return;
                    }
                }
                if (FileUpload3.FileName.ToString() != "")
                {
                    FileUpload3.SaveAs(Request.MapPath(FileUpload3.FileName));
                    Session["mmsFilePath3"] = Request.MapPath(FileUpload3.FileName);
                    FileInfo fileInfoObj = new FileInfo(Session["mmsFilePath3"].ToString());
                    fileSize = fileSize + fileInfoObj.Length / 1024;
                    if (fileSize > 600)
                    {
                        drawPanelForFailure(sendMessagePanel, "Attachment file size exceeded 600kb");
                        return;
                    }
                }
                if (fileSize <= 600)
                {
                    sendMms();
                }
                else
                {
                    drawPanelForFailure(sendMessagePanel, "Attachment file size exceeded 600kb");
                    return;
                }
            }
        }
        catch (Exception ex)
        {
            drawPanelForFailure(sendMessagePanel, ex.ToString());
            return;
        }
    }

    /* this function calls get message delivery status api to fetch the delivery status */
    private void getMmsDeliveryStatus()
    {
        try
        {
            string mmsId = messageIDTextBox.Text.ToString();
            if (mmsId == null || mmsId.Length <= 0)
            {
                drawPanelForFailure(getStatusPanel, "Message Id is null or empty");
                return;
            }
            if (readAndGetAccessToken(sendMessagePanel) == true)
            {
                if (access_token == null || access_token.Length <= 0)
                {
                    //drawPanelForFailure(sendSMSPanel, "Invalid access token");
                    return;
                }
                String mmsDeliveryStatus;
                HttpWebRequest mmsStatusRequestObject = (HttpWebRequest)System.Net.WebRequest.Create("" + FQDN + "/rest/mms/2/messaging/outbox/" + mmsId + "?access_token=" + access_token.ToString());
                mmsStatusRequestObject.Method = "GET";
                HttpWebResponse mmsStatusResponseObject = (HttpWebResponse)mmsStatusRequestObject.GetResponse();
                using (StreamReader mmsStatusResponseStream = new StreamReader(mmsStatusResponseObject.GetResponseStream()))
                {
                    mmsDeliveryStatus = mmsStatusResponseStream.ReadToEnd();
                    mmsDeliveryStatus = mmsDeliveryStatus.Replace("-", "");
                    JavaScriptSerializer deserializeJsonObject = new JavaScriptSerializer();
                    GetDeliveryStatus status = (GetDeliveryStatus)deserializeJsonObject.Deserialize(mmsDeliveryStatus, typeof(GetDeliveryStatus));
                    drawGetStatusSuccess(status.DeliveryInfoList.deliveryInfo[0].deliverystatus, status.DeliveryInfoList.resourceURL);
                    mmsStatusResponseStream.Close();
                }
            }
        }
        catch (Exception ex)
        {
            drawPanelForFailure(getStatusPanel, ex.ToString());
        }
    }
    /* this function draws table for get status result */
    private void drawGetStatusSuccess(string status, string url)
    {
        Table table = new Table();
        table.Font.Name = "Sans-serif";
        table.Font.Size = 9;
        table.BorderStyle = BorderStyle.Outset;
        table.Width = Unit.Pixel(650);
        TableRow rowOne = new TableRow();
        TableCell rowOneCellOne = new TableCell();
        rowOneCellOne.Font.Bold = true;
        rowOneCellOne.Text = "SUCCESS:";
        //rowOneCellOne.BorderWidth = 1;
        rowOne.Controls.Add(rowOneCellOne);
        table.Controls.Add(rowOne);
        TableRow rowTwo = new TableRow();
        TableCell rowTwoCellOne = new TableCell();
        TableCell rowTwoCellTwo = new TableCell();
        //rowTwoCellOne.BorderWidth = 1;
        rowTwoCellOne.Text = "Status: ";
        rowTwoCellOne.Font.Bold = true;
        rowTwo.Controls.Add(rowTwoCellOne);
        rowTwoCellTwo.Text = status.ToString();
        //rowTwoCellTwo.BorderWidth = 1;
        rowTwo.Controls.Add(rowTwoCellTwo);
        table.Controls.Add(rowTwo);
        TableRow rowThree = new TableRow();
        TableCell rowThreeCellOne = new TableCell();
        TableCell rowThreeCellTwo = new TableCell();
        rowThreeCellOne.Text = "ResourceURL: ";
        rowThreeCellOne.Font.Bold = true;
        //rowThreeCellOne.BorderWidth = 1;
        rowThree.Controls.Add(rowThreeCellOne);
        rowThreeCellTwo.Text = url.ToString();
        //rowThreeCellTwo.BorderWidth = 1;
        rowThree.Controls.Add(rowThreeCellTwo);
        table.Controls.Add(rowThree);
        table.BorderWidth = 2;
        table.BorderColor = Color.DarkGreen;
        table.BackColor = System.Drawing.ColorTranslator.FromHtml("#cfc");
        getStatusPanel.Controls.Add(table);
    }

    /* this function is called when user click on get status button */
    protected void getStatusButton_Click(object sender, EventArgs e)
    {
        getMmsDeliveryStatus();
    }
}

/* The following are data structures used for the application */
public class mmsResponseId
{
    public string id;
}

public class GetDeliveryStatus
{
    public DeliveryInfoList DeliveryInfoList = new DeliveryInfoList();
}
public class DeliveryInfoList
{
    public string resourceURL;
    public List<deliveryInfo> deliveryInfo { get; set; }
}

public class deliveryInfo
{
    public string id { get; set; }
    public string address { get; set; }
    public string deliverystatus { get; set; }
}

public class AccessTokenResponse
{
    public string access_token;
    public string refresh_token;
    public string expires_in;
}

Web.config

<?xml version="1.0"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  http://go.microsoft.com/fwlink/?LinkId=169433
  -->
<configuration>
  <system.web>
    <compilation debug="true" targetFramework="4.0"/>
    <customErrors mode="Off"></customErrors>
  </system.web>
  <appSettings>

    <!-- This is mandatory key and value should be equal
         to  MMS Service registered application 'API key'
         example: value="2726942c798aaaaa4bd3625d95cc7355"-->
    <add key="api_key" value=""/>

    <!-- This is mandatory key and value should be equal
         to  MMS Service registered application 'Secret key'
         example: value="5fb012657aaa6c7d"-->
    <add key="secret_key" value=""/>

    <!-- This is mandatory key and value should be equal
         to  MMS Service registered application 'short code'
         example: value="80750000" -->
    <add key="short_code" value=""/>

    <!-- This is mandatory key and value should be equal
         to  https://api.att.com for production environment
         example: value="https://api.att.com"-->
    <add key="FQDN" value=""></add>

    <!-- This is optional key and if you want to define, then the value should be equal
         to  "MMS"
         example: value="MMS"-->
    <add key="scope" value=""/>

    <!-- This is optional key, which points to the file path, and application uses this key's value to create/update 
         the file with access token information, so, make sure to give write access to the folder defined.
         If the key is not defined, MMSApp1AccessToken.txt will be created at root folder, so, make sure to give
         write access to the root folder
         example: value="~\\csharpapps\\mms\\app1\\MMSApp1AccessToken.txt"
         -->    
    <add key="AccessTokenFilePath" value =""/>
    
  </appSettings>
</configuration>