What Is View ? What Is Razor & Razor View Engine In ASP.Net MVC

What is a View ?

• View provides the UI (User Interface) of the application to the user.
• View is used to display content of an application and also to accept user inputs (Forms).
• View uses model data to create this UI (User Interface).
• View contains both HTML markup and C# code that runs on the Web server.
• View has a file extension .cshtml

What Is Razor ?

• Razor is a syntax, based on the ASP.NET Framework that allows creating views.
• Razor is simple and easy to understand for users who are familiar with the C#.NET or VB.NET programming languages.

Following code snippet shows a simple razor view containing both HTML markups for presentation and C# code:

The MVC Framework uses a view engine to convert the code of a view into HTML markup that a browser can understand.

What Is Razor View Engine ?

• Razor View Engine is used as the default view engine by the MVC Framework.
• Razor View Engine compiles a view of your application when the view is requested for the first time.
• Razor View Engine delivers the compiled view for subsequent requests until you make changes to the view.
• Razor View Engine does not introduce a new set of programming language, but provides template markup syntax to segregate HTML markup and programming code in a view.

A Razor

• First requires identifying the server-side code from the markup code to interpret the server-side code embedded inside a view file.
• Uses the @symbol, to separate the server-side code from the markup code.

While creating a Razor view, you should consider following rules:

• Enclose code blocks between @{ and }
• Start inline expressions with @
• Variables are declared with the var keyword
• Enclose strings in quotation marks ” “
• End a Razor code statement with semicolon (;)
• Use the .cshtml extension to store a Razor view file that uses C# as the programing language
• Use the .vbhtml extension to store a Razor view file that uses VB as the programing language.

In this lecture, we will learn

• Inline expression statement.
• Declaring variable using var keyword.
• Multi statement code block.
• Multi statement code block.
• Loops

Source Code Of HomeController

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;

namespace RazorSyntaxDemo.Controllers
{
    public class HomeController : Controller
    {
        // GET: Home
        public ActionResult Index()
        {
            return View();
        }
    }
}

Source Code Of View – Where We Write Razor Code

@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>

<!--Inline expression statement-->
 
@*<p>TODAY DATE AND TIME IS: @DateTime.Now</p>
<p>THIS YEAR IS @DateTime.Now.Year</p>*@

<!--declaring variables-->
@*@{ 
    string name = "Learning Never Ends";
    var TodaysTime = DateTime.Now.ToLongTimeString();
}

<h2>Channel name is: @name</h2>
<h2>Todays time is: @TodaysTime</h2>*@

<!--Conditional statements-->

@*@{
    int marks = 75;
    if(marks >= 80)
    {
        <h2>YOUR GRADE IS A-1</h2>
    }
    else
    {
        <h2>YOUR GRADE IS A</h2>
    }
}*@

@*@{ 
    string fruit = "orange";
    switch(fruit)
    {
        case "banana":
        <h2>YOU HAVE SELECTED BANANA</h2>
            break;

        case "strawberry":
            <h2>YOU HAVE SELECTED STRAWBERRY</h2>
            break;

        case "apple":
            <h2>YOU HAVE SELECTED APPLE</h2>
            break;

        default:
            <h2>INVALID FRUIT</h2>
            break;
    }
}*@

@*@{ 
    for (int i = 1; i < 10; i++)
    {
        <h2>@i</h2>
    }
}*@

@{ 
    string[] sports = {"FOOTBALL","CRICKET","HOCKEY","BASEBALL" };

    foreach (string i in sports)
    {
        <h2>@i</h2>
    }
}