Error After Upgrading the Blazor Project WASM to .Net 8 to .Net 9

Question

I got this errors While Upgrading my Blazor Web assembly Project to .Net 8 to .Net 9

Error
Message=   Source=   Stack Trace:   at

https://localhost:7123/_framework/dotnet.runtime.o8gq1i8bk6.js:3:96088

This Error  I got in console

MONO_WASM: instantiate_wasm_module() failed TypeError: Cannot read properties of undefined (reading 'promise')

 

Answer 1

Hi @Satyasai Gunnam，

When upgrading from .NET8 to .NET9, we not only need to adjust the Target framework, but also upgrade all packages to latest version.

For me, I upgraded below packages.

<PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" Version="9.0.0" />
<PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.DevServer" Version="9.0.0" PrivateAssets="all" />

You need to check it in Nuget Package Manager tool.

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Best regards,

Jason