What You Can & Cannot Do in CSHTML (Razor Views)

Below is a well-structured blog post explaining what is possible in CSHTML (Razor Views) and what is NOT possible compared to ASP.NET Web Forms, along with examples, attributes, and key concepts.

ASP.NET Core MVC introduced Razor View Engine (CSHTML files), replacing the old ASP.NET Web Forms (.aspx, .ascx) system.

Many developers coming from Web Forms often get confused:

“Where is GridView? Where is DataBind()? Can I use UpdatePanel? Why can't I drag and drop controls?”

This blog post clears all doubts with examples, comparisons, and CSHTML capabilities.

1. What Is CSHTML in ASP.NET Core?

CSHTML = C# + HTML
It is a Razor template file that allows embedding C# code inside HTML in a clean, lightweight way.

Example

@{
    var message = "Hello Razor!";
}

<h2>@message</h2>

Razor follows the philosophy:

“Generate HTML using C#, but keep UI logic minimal and clean.”

2. CSHTML vs Web Forms — Key Differences

Feature	CSHTML (Razor)	Web Forms (ASPX)
Server Controls	Not supported	GridView, Repeater, TextBox, Button
ViewState	No ViewState	Heavy ViewState
Auto Postback	Not supported	AutoPostback events
Drag-and-drop UI	No	Yes
DataBind()	Not available	Required
Page Life Cycle	No page events	Page_Load, PreInit, OnInit
Data Binding	Modern Razor binding	Server data controls binding
HTML control freedom	Full control	Limited
Performance	Very fast, lightweight	Slow because of ViewState

3. What IS POSSIBLE in CSHTML (Razor)?

3.1 Use loops (for, foreach, while)

Example

@foreach (var item in Model)
{
    <p>@item.Name</p>
}

3.2 Conditionals (if/else, switch)

@if (Model.IsActive)
{
    <span class="badge bg-success">Active</span>
}
else
{
    <span class="badge bg-danger">Inactive</span>
}

3.3 Strongly Typed Models

@model IEnumerable<Product>

You can bind data directly without DataBind().

3.4 Tag Helpers (Modern equivalent of server controls)

Example: Action link button

<a asp-action="Details" asp-route-id="@item.Id">View</a>

Form Tag Helper:

<form asp-action="Create" method="post">

Input Tag Helper:

<input asp-for="Name" class="form-control" />

3.5 Partial Views (instead of UserControls)

@await Html.PartialAsync("_ProductCard", product)

3.6 Sections and Layouts

Reusable layout like MasterPage:

@layout "~/Views/Shared/_Layout.cshtml"

3.7 AJAX & jQuery instead of UpdatePanel

Example AJAX call:

$.get("/Product/GetStock/5", function(data) {
    $("#stockDiv").html(data);
});

4. What is NOT Possible in CSHTML (Compared to Web Forms)

4.1 No Server Controls (GridView, Repeater, DropDownList etc.)

You cannot do:

<asp:GridView ID="grid1" runat="server" AutoGenerateColumns="true" />

Instead you must build HTML manually:

<table>
@foreach (var item in Model)
{
    <tr><td>@item.Name</td></tr>
}
</table>

4.2 No ViewState

Meaning:

No automatic state management
No hidden page lifecycle data
Much faster performance

4.3 No AutoPostBack

You cannot do:

AutoPostBack="true"
OnSelectedIndexChanged="ddlChanged"

You must use:

1.JavaScript

2.jQuery

3.AJAX

4.Fetch API

4.4 No Page Life Cycle Events

No such events:

Page_Load
Page_Init
Page_PreRender

Instead ASP.NET Core uses:

1. Controller actions

2. Dependency Injection

3. Middleware

4.5 No UpdatePanel

UpdatePanel was used for partial page refresh.
In MVC Core, you must use:

AJAX
Fetch API
jQuery
Partial Views
HTMX / SignalR

5. Examples: How CSHTML Replaces Web Forms Controls

Example 1: GridView → Razor Table

Web Forms GridView

<asp:GridView ID="grid" runat="server" AutoGenerateColumns="true">
</asp:GridView>

Razor (CSHTML)

<table class="table table-bordered">
@foreach (var item in Model)
{
    <tr>
        <td>@item.Name</td>
        <td>@item.Price</td>
    </tr>
}
</table>

Example 2: UserControl → Partial View

Web Forms

<uc1:ProductDetail ID="ProductDetail1" runat="server" />

Razor

@await Html.PartialAsync("_ProductDetail", Model)

Example 3: UpdatePanel → AJAX

Web Forms

<asp:UpdatePanel runat="server">
   <ContentTemplate>

Razor + jQuery

$("#loadBtn").click(function () {
    $("#result").load("/Product/Partial");
});

6. Attributes in Razor (Tag Helpers)

Attribute	Purpose
asp-for	Binds to model property
asp-action	Calls controller action
asp-controller	Specifies controller
asp-route-id	Pass route parameter
asp-validation-for	Shows validation errors
asp-items	Binds dropdown values

Example

<select asp-for="CategoryId" asp-items="Model.Categories"></select>

7. Summary — Quick Comparison

Razor CSHTML Allows

HTML + C#
Loops, conditions
Models
Tag Helpers
Partial Views
AJAX
Custom HTML UI

Razor Does NOT Allow:

GridView, Repeater, DataList
UpdatePanel
ViewState
Code-behind UI logic
Drag-and-drop server controls