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The project is a wpf desktop application. I only get one bad error:
Unknown build error, 'Could not find type 'System.Web.UI.TagPrefixAttribute' in assembly 'C:\Program Files\dotnet\packs\Microsoft.NETCore.App.Ref\6.0.6\ref\net6.0\System.Web.dll'.' C:\Program Files\dotnet\sdk\6.0.301\Sdks\Microsoft.NET.Sdk.WindowsDesktop\targets\Microsoft.WinFX.targets
The only web access the application makes is to an email verification site using SingleRequestModel.
I have searched other sites and found some other pages that address this issue but only for Web applications. What is a fix - or at least a workaround - for this bug.
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HI,@RogerSchlueter-7899 . For System.Web.UI.TagPrefixAttribute Class, it is applicable to .NET Framework 1.1-4.8 version. Are you directly referencing System.Web in your WPF project? If so, you could try to remove this dependency before migrating. Are there any third-party components in your project before migrating?
There is no reference to System.Web, confirmed by doing a solution-side search with no result.
I do use some third-party tools but none of them relating to the web at all ... although I suppose it's possible.
I think I'll start a new project, and one piece at a time from my existing project until that error arises.
Stand by ..........
The problem arises because I use the Bing Maps REST Toolkit which, apparently, uses that class. Omitting the window which draws maps, the error goes away.
However, the GitHub page (https://github.com/microsoft/BingMapsRESTToolkit) says that ".NET Standard 2.0+" is supported so I don't understand why I'm getting this error. Do you have any suggestions on how I should proceed other than going back to 4.8.
TagPrefixAttribute is a class in system.web.ui and not compatible with .net 6. Do you have anything like this in your code?
[assembly:TagPrefix("CustomControls", "custom")]
No, nothing like that. I looked at the System.Web.UI Namespace where it says it supports "ASP.NET Web applications." As I mentioned, my app is a desktop app. I'm puzzled.
See my comment above.
Hi,@RogerSchlueter-7899 . The problem may be a build error due to a transitive dependency on System.Web.
There may also be item does not create the correct structure for the project. Either the third party, studio, nuget packages/manager. You could also try to manually restructure the project files to the correct target framework.
Those possibilities are above my skill level. I'm going to look at other mapping tools.
Hi,@RogerSchlueter-7899 . I'd love to hear any updates on the issue, or if the issue has been resolved.