[Problem/Bug]: "WebView2" does not exist in namespace "clr-namespace:Microsoft.Web.WebView2.Wpf;

[intrix-bob]

What happened?

Error while compiling .net wpf application using WebView2-Control: "WebView2" does not exist in namespace "clr-namespace:Microsoft.Web.WebView2.Wpf;

Visual Studio 2022: Project .net 8 (limited to Windows 10, X64)

Importance

Important. My app's user experience is significantly compromised.

Runtime Channel

Stable release (WebView2 Runtime)

Runtime Version

1.02849.39

SDK Version

.net 8

Framework

WPF

Operating System

Windows 10

OS Version

No response

Repro steps

with actual Release it doesn't work
With old "1.0.2478.35" no compile errors

Repros in Edge Browser

Yes, issue can be reproduced in the corresponding Edge version

Regression

Regression in newer Runtime

Last working version (if regression)

1.0.2478.35

[sandeepchads]

The error message "WebView2 does not exist in namespace clr-namespace:Microsoft.Web.WebView2.Wpf" typically indicates that the WebView2 control is not properly referenced in your project. Here are some steps to troubleshoot and resolve this issue:

1. Ensure the NuGet Package is Installed:

   • Make sure you have installed the Microsoft.Web.WebView2 NuGet package in your project. You can do this via the NuGet Package Manager or by running the following command in the Package Manager Console:

2. Check the Project References:

   • Verify that your project references the Microsoft.Web.WebView2.Wpf assembly. You can do this by right-clicking on your project in Solution Explorer, selecting "Add Reference," and ensuring that the Microsoft.Web.WebView2.Wpf assembly is listed and checked.

3. Add the Correct XML Namespace:

   • Ensure that you have added the correct XML namespace in your XAML file. It should look something like this:

4. Clean and Rebuild Your Project:

   • Sometimes, Visual Studio needs a clean build to recognize new references. Go to "Build" -> "Clean Solution" and then "Build Solution."
     This is a common fix for such issues.

Let me know if you need further assistance!

[intrix-bob]

No, I tried to update with nuget to the library to curret version 2849 - then there are no compile time assemblies (.core, winforms,wpf).
Then I switched back to an older version (2592). All is fine an the assiblies are here.
Allways tried to clean, rebuild and so on.

[jovienclauzade]

I've been facing the exact same issue on my side.
I managed to pinpoint the exact version at which it started to be broken : 1.0.2651.64 and latest
Previously I've been using 1.0.2478.35 without any problem.

(tried every versions between 1.0.2478.35 and the current latest, cleaning the full solution cache + rebuilding the solution every time).

(on net9.0-windows TFM)

[dlemstra]

I can confirm downgrading to 1.0.2478.35 resolves the build error on a hosted Azure DevOps build agent (version 4.255.0). We also tried creating the component in code instead of the .xaml file but that result in this build error:

Error CS0246: The type or namespace name 'WebView2' could not be found

Building locally in Visual Studio 2022 works. A build where we target net8.0 with msbuild on the an Azure DevOps build agent result in build errors. Is there anything extra that we need to do on the build agent @sandeepchads?

[Badhri]

@dlemstra @intrix-bob Could you please provide a sample repro solution for us to try on our end ?

[dlemstra]

I have created a project that demonstrates this issue: https://github.com/dlemstra/WebView2BuildIssue. I have create both a pipeline for AzureDevOps and for GitHub and both of them fail @Badhri. You can see the GitHub pipeline here: https://github.com/dlemstra/WebView2BuildIssue/actions.

[Badhri]

@dlemstra We downloaded the sample project and tried it locally in visual studio(in both windows10 and windows 11).
Both the nuget versions 1.0.2849.39 and latest version 1.0.3240.44 is working fine and we are not able to reproduce this compile error.
Could you please try this once locally in visual studio and help us if we are missing something ?

[dlemstra]

The issue is that this works locally on my machine but fails to build in either an Azure DevOps or GitHub pipeline. So what do we need to do to make this work in the pipelines?

[Badhri]

@dlemstra We have created an internal tracking bug to check this failure in pipeline. Will post the update here once this is fixed.

[Badhri]

@dlemstra We have created an internal tracking bug to check this failure in pipeline. Will post the update here once this is fixed.

Here is the link to internal tracking bug