WebFormsForCore

A library to run WebForms apps on ASP.NET Core. This library provides a port of the System.Web libraries of .NET Framework to .NET 8. With this library, you can run WebForms websites directly in ASP.NET Core, also on Linux.

Support

If you need support porting your project to NET Core & WebFormsForCore, we provide support for 40$ per hour. Please contact us via Messenger. There is also a tutorial on Youtube on how to convert a sample WebForms application to WebFormsForCore.

Usage

If you have a WebForms project you want to convert to NET Core, proceed as follows:

First convert your Project to a SDK Project. Please keep a backup of the old non SDK style project. Conversion can be done easiest by using a converter like the migrate-2019 tool. To install that tool, run dotnet tool install --global Project2015To2017.Migrate2019.Tool. Then go to the directory of your solution and run dotnet migrate-2019 wizard to convert your solution to an SDK project. If the converter complains about an unsupported project type, remove the <ProjectTypeGuid> property from the project first. After conversion change the target framework of your project to net8.0. You might also keep net48, in order to dual run your project with NET Framework & NET Core. Change the OutputPath for net8.0 to bin_dotnet:

<PropertyGroup>
    <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
    <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
    <!-- Set base intermediate output path, so NET Core build does not conflict with NetFX build. -->
    <BaseIntermediateOutputPath>obj\$(Configuration)\$(TargetFramework)\</BaseIntermediateOutputPath>
</PropertyGroup>

<PropertyGroup Condition="'$(TargetFramework)' != 'net48'">
    <OutputType>Exe</OutputType>
    <OutputPath>bin_dotnet</OutputPath>
    <StartupObject>Program</StartupObject>
</PropertyGroup>

<PropertyGroup Condition="'$(TargetFramework)' == 'net48'">
    <OutputType>Library</OutputType>
    <OutputPath>bin</OutputPath>
</PropertyGroup>

Then, for net8.0, import the WebFormsForCore packages like so:

<ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
    <PackageReference Include="EstrellasDeEsperanza.WebFormsForCore.Web" Version="1.0.0" />
</ItemGroup>

Remove the old Reference references or put them in a condition only for net48.

If your project also needs System.Web.Extensions or System.Web.Optimization import the corresponding packages also, like EstrellasDeEsperanza.WebFormsForCore.Web.Extensions or EstrellasDeEsperanza.WebFormsForCore.Web.Optimization etc. The following packages are available:

• System.Configuration: EstrellasDeEsperanza.WebFormsForCore.Configuration
• System.Web: EstrellasDeEsperanza.WebFormsForCore.Web
• System.Web.Services: EstrellasDeEsperanza.WebFormsForCore.Web.Services
• System.Web.Extensions: EstrellasDeEsperanza.WebFormsForCore.Web.Extensions
• System.Web.Optimization: EstrellasDeEsperanza.WebFormsForCore.Web.Optimization
• System.Web.Mobile: EstrellasDeEsperanza.Web.Mobile
• Microsoft.AspNet.Web.Optimization.WebForms: EstrellasDeEsperanza.WebFormsForCore.Web.Optimization.WebForms
• WebGrease: EstrellasDeEsperanza.WebFormsForCore.WebGrease
• System.Drawing: EstrellasDeEsperanza.WebFormsForCore.Drawing
• AjaxControlToolkit: EstrellasDeEsperanza.WebFormsForCore.AjaxControlToolkit
• AjaxControlToolkit.HtmlEditor.Sanitizer: EstrellasDeEsperanza.WebFormsForCore.AjaxControlToolkit.HtmlEditor.Sanitizer
• AjaxControlToolkit.StaticResources: EstrellasDeEsperanza.WebFormsForCore.AjaxControlToolkit.StaticResources

System.Drawing only implements Attributes, so WebFormsForCore can run on Linux, where System.Drawing.Common.dll is missing.

If you want WebFormsForCore to automatically create the *.designer.cs files for you, as it was in the old non SDK project, you also need to import the package EstrellasDeEsperanza.WebFormsForCore.Build. If you import this package, outdated *.designer.cs files will be created after build. This only works for C#, not for VisualBasic. Also, the visual designers in VisualStudio for web controls are not supported and won't work.

Finally configure ASP-NET Core to use WebForms in the initialization code Program.cs like so:

#if NETCOREAPP

using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.DependencyInjection;

public class Program
{

	public static void Main(string[] args)
	{
		var builder = WebApplication.CreateBuilder(args);

		// Add services to the container.
		builder.Services.AddRazorPages();
		builder.Services.AddControllersWithViews();

		var app = builder.Build();

		app.UseStaticFiles();

		//app.UseAuthorization();

		//app.MapDefaultControllerRoute();
		
        app.UseWebForms();
			
		app.Run();

	}
}
#endif

Conflicts with Existing Packages

Currently there might be some conflicts with the packages System.Web.dll, System.Drawing.dll & System.Configuration.ConfigurationManager.dll, since WebFormsForCore replaces those dll's. In order to prevent import of the old dll's include the following in your csproj:

<Target Name="ChangeAliasesOfNugetRefs" BeforeTargets="FindReferenceAssembliesForReferences;ResolveReferences">
    <ItemGroup>
        <!-- Do not import System.Configuration.ConfigurationManager version 8 -->
        <ReferencePath Remove="%(Identity)" Condition="'%(FileName)' == 'System.Configuration.ConfigurationManager' AND $([System.Text.RegularExpressions.Regex]::IsMatch(%(Identity),'\\8[.0-9]+\\'))" />
        <!-- Do not import System.Web -->
        <ReferencePath Remove="%(Identity)" Condition="'%(FileName)' == 'System.Web' AND $([System.Text.RegularExpressions.Regex]::IsMatch(%(Identity),'\\dotnet\\'))" />
        <!-- Do not import System.Drawing -->
        <ReferencePath Remove="%(Identity)" Condition="'%(FileName)' == 'System.Drawing' AND $([System.Text.RegularExpressions.Regex]::IsMatch(%(Identity),'\\dotnet\\'))" />
    </ItemGroup>
</Target>