获取“类型'SpatialReference' 是在未引用的程序集中定义的。” 仅当优化代码未选中时

Question

I'm getting a weird compilation error and I'm just utterly baffled by it.

When I compile my project, I get this:

The type 'SpatialReference' is defined in an assembly that is not referenced. You must add a reference to assembly 'Esri.ArcGISRuntime, Version=10.2.7.0, Culture=neutral, PublicKeyToken=8fc3cc631e44ad86'.

That's not the weird part though. I only get this when I have "Optimize Code" unchecked in the C# project settings for the application.

When I check the "Optimize Code" checkbox, it compiles just fine, and the application runs as expected.

The type 'SpatialReference' is not being used in the application at all, and that particular type is wrapped up in another assembly referenced by the application, and as far as I can see the type is not leaking out from the wrapper code.

Other applications that use this same wrapper assembly will compile with no issues, regardless of the Optimize Code state, and the wrapper assembly has been in use for almost 5 years without issue.

Has anyone else ran into this problem? If so, how'd you fix it?

Just for reference, these applications are WinForms applications. And I'm using Visual Studio 2019 Enterprise, v16.8.1

Update 2020-11-22

After uninstalling 16.8 from our build machine (which was affected by this) and putting 16.7.7 back on, it compiles just fine. This is starting to look like a problem with v16.8.x.

I should note the following:

• The projects are windows forms applications running under .NET 4.7.2
• My personal work machine with 16.8 fails to build, the build machine for our CI with 16.8 fails, but my coworker's machine with 16.7.7 works.
• This only affects 1 project out of 10 projects, all of which use the same wrapper API and the same functionality, and no changes have been made to the wrapper in ages. Why it fails with just one and not the others is unknown.

I've been through the csproj file (using a text editor) for the failing project with a fine tooth comb and I have not seen anything out of the ordinary.

Answer 1

Please firstly try to clear the NuGet cache and then reinstall NuGet packages, if you installed some NuGet packages for example Esri.ArcGISRuntime .

For clearing NuGet cache, please go to Tools > Options > NuGet Package Manager > General > Package Restore > select “Allow NuGet to download missing packages” and “Automatically check for missing packages during build in Visual Studio” > then click Clear All NuGet Cache(s) button.

For reinstalling NuGet packages, please go to Tools > NuGet Package Manager > Package Manager Console > in Package Manager Console enter Update-Package -reinstall to reinstall the NuGet packages.

After that, please restart VS and rebuild your project, check if this issue disappears. If this issue still persists, please try following steps to troubleshoot:

1). Please close every VS instances and go to your solution folder, then rename(or delete) the hidden .vs , bin and obj folders, after that launch VS and rebuild your solution.

2). Please go to this path: C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\VisualStudio\\16.0_XXXX and rename(or delete) every folders named “ComponentModelCache”.

3). Please disable any third-party extensions temporarily from Extensions > Manage Extensions > Installed > Disable and test again.

4). Please kindly try to repair Visual Studio 2019 from Visual Studio Installer > VS 2019 > More > Repair.