ASP.NET Razor - C# Code Syntax - PDF Download Cheatsheet

Index

Razor Comments
Inline expression
Multi-statement block
Store String
Store Date
Store Date
Variables
Convert Data Types
Loops
Arrays
Conditionals
Using
Models View
Dependency Injection
Add Functions
Create Templates
Conditional Attributes
Forms
Add Partials
Add link to a page
Loop through a list and output

Razor is a markup syntax that lets you embed server-based code (Visual Basic and C#) into web pages

Razor Comments

@*  A one-line code comment. *@

@*
    This is a multiline code comment.
    It can continue for any number of lines.
*@

@{
    @* This is a comment. *@
    var theVar = 17;
}

Single statement block

@{ var myMessage = "Hello World"; }

Inline expression

@{ var myMessage = "Hello World"; }

Multi statement block

@{
var greeting = "Welcome to our site!";
var weekDay = DateTime.Now.DayOfWeek;
var greetingMessage = greeting + " Here in Huston it is: " + weekDay;
}
<p>The greeting is: @greetingMessage</p> }

Store String

/* A string is a sequence of characters that are treated as text. To specify a string, you enclose it in double quotation marks:*/

@{ var welcomeMessage = "Welcome, new members!"; }
<p>@welcomeMessage</p>

Store Date

@{ var year = DateTime.Now.Year; }

Read User Input

@{
var totalMessage = "";
if(IsPost)
    {
    var num1 = Request["text1"];
    var num2 = Request["text2"];
    var total = num1.AsInt() + num2.AsInt();
    totalMessage = "Total = " + total;
}
}

Variables

@{
    // Assigning a string to a variable.
    var greeting = "Welcome!";

    // Assigning a number to a variable.
    var theCount = 3;

    // Assigning an expression to a variable.
    var monthlyTotal = theCount + 5;

    // Assigning a date value to a variable.
    var today = DateTime.Today;

    // Assigning the current page's URL to a variable.
    var myPath = this.Request.Url;

    // Declaring variables using explicit data types.
    string name = "Joe";
    int count = 5;
    DateTime tomorrow = DateTime.Now.AddDays(1);
}

Display Variables

@{
    // Embedding the value of a variable into HTML markup.
    <p>@greeting, friends!</p>

    // Using variables as part of an inline expression.
    <p>The predicted annual total is: @( monthlyTotal * 12)</p>

    // Displaying the page URL with a variable.
    <p>The URL to this page is: @myPath</p>
}

Convert Data Types

Method	Description	Examples
AsInt(), IsInt()	Converts a string to an integer.	`if (myString.IsInt())` `{myInt=myString.AsInt();`
AsFloat(), IsFloat()	Converts a string to a floating-point number.	`if (myString.IsFloat())` `{myFloat=myString.AsFloat();}`
AsDecimal(), IsDecimal()	Converts a string to a decimal number..	`if (myString.IsDecimal())` `{myDec=myString.AsDecimal();}`
AsDateTime(), IsDateTime()	Converts a string to an ASP.NET DateTime type.	`myString="10/10/2012";` `myDate=myString.AsDateTime();`
AsBool(), IsBool()	Converts a string to a Boolean..	`myString="True";` `myBool=myString.AsBool();`
ToString()	Converts any data type to a string.	`myInt=1234;` `myString=myInt.ToString();`

Coverting Data Types example

@{
    var total = 0;

    if(IsPost) {
        // Retrieve the numbers that the user entered.
        var num1 = Request["text1"];
        var num2 = Request["text2"];
        // Convert the entered strings into integers numbers and add.
        total = num1.AsInt() + num2.AsInt();
    }
}

Loops

Standard Loop

@for (var i = 0; i < people.Length; i++)
{
    var person = people[i];
    <text>Name: @person.Name</text>
}

ForEach Loops

<ul>
@foreach (var myItem in Request.ServerVariables)
{
    <li>@myItem</li>
}
</ul>

While Loops

@{
    var countNum = 0;
    while (countNum < 50)
    {
        countNum += 1;
        <p>Line #@countNum: </p>
    }
}

Arrays

@{
string[] members = {"Jani", "Hege", "Kai", "Jim"};
int i = Array.IndexOf(members, "Kai")+1;
int len = members.Length;
string x = members[2-1];
}
<html>
<body>
<h3>Members</h3>
@foreach (var person in members)
{
<p>@person</p>
}
<p>The number of names in Members are @len</p>
<p>The person at position 2 is @x</p>
<p>Kai is now in position @i</p>
</body>
</html>

Conditionals

If

@{
  var showToday = true;
  if(showToday)
  {
    @DateTime.Today;
  }
}

If Else

@{
  var showToday = false;
  if(showToday)
  {
    @DateTime.Today;
  }
  else
  {
    <text>Sorry!</text>
  }
}

Else If

@{
    var theBalance = 4.99;
    if(theBalance == 0)
    {
        <p>You have a zero balance.</p>
    }
    else if (theBalance  > 0 && theBalance <= 5)
    {
        <p>Your balance of $@theBalance is very low.</p>
    }
    else
    {
        <p>Your balance is: $@theBalance</p>
    }
}

Switch Statement

@{
    var weekday = "Wednesday";
    var greeting = "";

    switch(weekday)
    {
        case "Monday":
            greeting = "Ok, it's a marvelous Monday";
            break;
        case "Tuesday":
            greeting = "It's a tremendous Tuesday";
            break;
        case "Wednesday":
            greeting = "Wild Wednesday is here!";
            break;
        default:
            greeting = "It's some other day, oh well.";
            break;
    }

    <p>Since it is @weekday, the message for today is: @greeting</p>
}

Try Catch Finally

@try
{
    throw new InvalidOperationException("You did something invalid.");
}
catch (Exception ex)
{
    <p>The exception message: @ex.Message</p>
}
finally
{
    <p>The finally statement.</p>
}

Using

/* The @using directive adds the C# using directive to the generated view:*/

@using System.IO
@{
    var dir = Directory.GetCurrentDirectory();
}
<p>@dir</p>

Models View

// The @model directive specifies the type of the model passed to a view:

@model TypeNameOfModel

Access Model

<div>The Login Email: @Model.Email</div>

Dependency Injection

@inject +ServiceName

Add Functions

@functions {
    public string GetHello()
    {
        return "Hello";
    }
}

<div>From method: @GetHello()</div>

Create Templates

Create a class

public class Pet
{
    public string Name { get; set; }
}

create a .cshtml page

@{
    Func<dynamic, object> petTemplate = @<p>You have a pet named @item.Name.</p>;

    var pets = new List<Pet>
    {
        new Pet { Name = "Rin Tin Tin" },
        new Pet { Name = "Mr. Bigglesworth" },
        new Pet { Name = "K-9" }
    };

     <!-- The template is rendered with pets supplied by a foreach statement: -->

     @foreach (var pet in pets)
{
    @petTemplate2(pet)
}
}

Rendered output

<p>You have a pet named <strong>Rin Tin Tin</strong>.</p>
<p>You have a pet named <strong>Mr. Bigglesworth</strong>.</p>
<p>You have a pet named <strong>K-9</strong>.</p>

Conditional Attributes

@{
    string divStyle = null;
    if(Request.QueryString["style"] != null)
    {
        divStyle = "background-color: yellow;";
    }
}
<div style="@divStyle">Hello, world!</div>

Forms

<form method="post">
            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
            <div class="form-group">
                <label asp-for="Movie.Title" class="control-label"></label>
                <input asp-for="Movie.Title" class="form-control" />
                <span asp-validation-for="Movie.Title" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="Movie.ReleaseDate" class="control-label"></label>
                <input asp-for="Movie.ReleaseDate" class="form-control" />
                <span asp-validation-for="Movie.ReleaseDate" class="text-danger"></span>
            </div>           
            <div class="form-group">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
</form>

Add Partials

@section Scripts {
    @{await Html.RenderPartialAsync("_ValidationScriptsPartial");}
}

Add link to a page

<div>
    <a asp-page="./Index">Back to List</a>
</div>

Loop through a list and output

<tbody>
        @foreach (var item in Model.Movie)
        {
            <tr>
                <td>
                    @Html.DisplayFor(modelItem => item.Title)
                </td>
                <td>
                    @Html.DisplayFor(modelItem => item.ReleaseDate)
                </td>
                <td>
                    @Html.DisplayFor(modelItem => item.Genre)
                </td>
                <td>
                    @Html.DisplayFor(modelItem => item.Price)
                </td>
                <td>
                    <a asp-page="./Edit" asp-route-id="@item.ID">Edit</a> |
                    <a asp-page="./Details" asp-route-id="@item.ID">Details</a> |
                    <a asp-page="./Delete" asp-route-id="@item.ID">Delete</a>
                </td>
            </tr>
        }
    </tbody>

jetstreamin/README.md

ASP.NET Razor - C# Code Syntax - PDF Download Cheatsheet

Index

Razor is a markup syntax that lets you embed server-based code (Visual Basic and C#) into web pages

Razor Comments

Single statement block

Inline expression

Multi statement block

Store String

Store Date

Read User Input

Variables

Display Variables

Convert Data Types

Coverting Data Types example

Loops

Standard Loop

ForEach Loops

While Loops

Arrays

Conditionals

If

If Else

Else If

Switch Statement

Try Catch Finally

Using

Models View

Access Model

Dependency Injection

Add Functions

Create Templates

Conditional Attributes

Forms

Add Partials

Add link to a page

Loop through a list and output