Paystack .NET Event Handling

MyHashHMAC.cs

using System;
					
public class MyHashHMACTester
{
	public static void Main()
	{
		// Usage sample
		Console.WriteLine(MyHashHMAC.sha512WithKey("{\"event\":\"charge.success\",\"data\":{\"id\":708206,\"domain\":\"test\",\"status\":\"success\",\"reference\":\"AB8760\",\"amount\":9000,\"message\":null,\"gateway_response\":\"Successful\",\"paid_at\":\"2017-02-02T08:18:39.000Z\",\"created_at\":\"2017-02-02T08:18:13.000Z\",\"channel\":\"card\",\"currency\":\"NGN\",\"ip_address\":\"154.118.4.232\",\"metadata\":{\"cancel_action\":\"https://gbeta.gigm.com/PayStack-Response.aspx\",\"custom_fields\":[],\"referrer\":\"http://gbeta.gigm.com/Passenger-Details.aspx\"},\"log\":{\"time_spent\":22,\"attempts\":1,\"authentication\":null,\"errors\":0,\"success\":false,\"mobile\":false,\"input\":[],\"channel\":null,\"history\":[{\"type\":\"input\",\"message\":\"Filled these fields: card number, card expiry, card cvv\",\"time\":22},{\"type\":\"action\",\"message\":\"Attempted to pay\",\"time\":22}]},\"fees\":null,\"fees_split\":null,\"customer\":{\"id\":167423,\"first_name\":null,\"last_name\":null,\"email\":\"[email protected]\",\"customer_code\":\"CUS_v636z2w7kvztrfe\",\"phone\":null,\"metadata\":null,\"risk_action\":\"default\"},\"authorization\":{\"authorization_code\":\"AUTH_ahil74ij\",\"bin\":\"412345\",\"last4\":\"1381\",\"exp_month\":\"01\",\"exp_year\":\"2020\",\"card_type\":\"visa visa\",\"bank\":\"TEST BANK\",\"country_code\":\"NG\",\"brand\":\"visa\",\"reusable\":true},\"plan\":{},\"subaccount\":{},\"paidAt\":\"2017-02-02T08:18:39.000Z\"}}", "sk_test_811ea39163d21a9625dd9b5cb9a791522d89b824"));
	}
}

public class MyHashHMAC
{
	
	public static string sha512WithKey(string message, string key)
	{
		System.Text.UTF8Encoding encoding=new System.Text.UTF8Encoding(); 
		byte [] keyByte = encoding.GetBytes(key);
	
		System.Security.Cryptography.HMACSHA512 hmacsha512 = new System.Security.Cryptography.HMACSHA512(keyByte);
	
		byte[] messageBytes = encoding.GetBytes(message); 
		byte[] hashmessage = hmacsha512.ComputeHash(messageBytes); 
		return ByteToString(hashmessage);
	}
	
	public static string ByteToString(byte [] buff)
	{
		string sbinary="";
	
		for (int i=0;i<buff.Length;i++)
		{
			sbinary+=buff[i].ToString("X2"); // hex format
		}
		return(sbinary);
	}
}

Page.cs

using System;
	          
protected void Page_Load(object sender, EventArgs e)
{
    MemoryStream memstream = new MemoryStream();
    Request.InputStream.CopyTo(memstream);
    memstream.Position = 0;
    using (StreamReader reader = new StreamReader(memstream))
    {
        string text = reader.ReadToEnd();
        // text comes escaped, let us return it to normal
        paystackValuesStringified = Regex.Replace(text, "(\"(?:[^\"\\\\]|\\\\.)*\")|\\s+", "$1");
          
    }
}

Hi Ibrahim, I'm trying to implement paystack for a aspx website project on localhost but it seems not to be accepting inputs from client side. Do you have any idea of what I'm not doing right.