WebForms on ASP.NET Core

The goal of this project is to explore building some of the basic building blocks of the WebForms on ASP.NET Core. This will isolate out the actual components needed to build a functional page.

Supported so far:

System.Web.IHttpHandler
System.Web.UI.Page
System.Web.UI.HtmlTextWriter
System.Web.UI.HtmlControls.*
System.Web.UI.WebControls.*
System.Web.Routing.*
Master pages
Compilation of aspx pages (both VB and C#)
Binary compatibility with System.Web.dll and System.Web.Extensions.dll (if the API exists)
ScriptManager and ajax support
System.Web.Optimization

What is NOT supported:

Designer support
System.Web hosting model
System.Web membership model
Any System.Web concept not called out as in scope

This will make use of Microsoft.AspNetCore.SystemWebAdapters to provide the System.Web.HttpContext that is at the core of the WebForms pipeline.

Get Started

Important

The feed URL has changed as of 2 April, 2024

Add a nuget.config or update yours to have the ci feed:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <packageSources>
    <!--To inherit the global NuGet package sources remove the <clear/> line below -->
    <clear />
    <add key="nuget" value="https://api.nuget.org/v3/index.json" />
    <add key="corewebforms" value="https://corewebformsfeed.blob.core.windows.net/feed/index.json" />
  </packageSources>
</configuration>

Create a .NET 8 project similar to the following with the WebForms SDK:

<Project Sdk="CoreWebForms.Sdk/0.2.1">

    <PropertyGroup>
        <TargetFrameworks>net8.0</TargetFrameworks>
        <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
        <!-- Optional, but easier to debug at runtime than compile time -->
        <EnableRuntimeAspxCompilation>true</EnableRuntimeAspxCompilation>
    </PropertyGroup>

</Project>

Add WebForms to your services (this automatically will add the System.Web adapters - this can be configured independently if needed)

    builder.Services.AddSystemWebAdapters()
        .AddPreApplicationStartMethod(false) // Used if you want to run any pre application start methods
        .AddJsonSessionSerializer()
        .AddWrappedAspNetCoreSession()
        .AddRouting()
        .AddWebForms()
        .AddScriptManager() // Remove if you don't use ScriptManager/AJAX
        .AddOptimization() // Remove if you don't use System.Web.Optimization
        .AddDynamicPages() // Used if you have dynamic pages
        .AddCompiledPages(); // Used if compiled pages are used

builder.Services.AddSession();
builder.Services.AddDistributedMemoryCache();

Add the System.Web middleware and map endpoints:

...
app.UseSession();
app.UseSystemWebAdapters();
...
app.MapHttpHandlers(); // Required for pages (or other configured handlers)
app.MapScriptManager(); // Required if you want to use ScriptManager
app.MapBundleTable(); // Required if you want to use BundleTable.Bundles

Add any .aspx or .aspx.cs/.aspx.vb files to your project. They should be served up as expected when you run.

Samples

For samples, please go to the samples repo for up-to-date examples.

Design docs

Please see the design docs to see the designs and plans for how this are expected to work.

birojnayak/CoreWebForms

WebForms on ASP.NET Core

Get Started

Samples

Design docs