C# Visual Studio项目中个人.config文件失效的原因及配置方法

Since your App.Base.config + App.Debug.Yaroslav.config setup works perfectly, the issue almost certainly boils down to missing or incorrect configuration in your project file for the Business.config set. Let’s walk through the most common fixes step by step:

1. Check Your .csproj File for Transformation Rules #

Your App configs are probably defined in the project file with explicit transformation settings—your Business configs are likely missing these. Here’s how to fix it:

• Unload your project in Visual Studio (right-click the project → Unload Project).
• Right-click the unloaded project → Edit [YourProjectName].csproj.
• Search for the section that handles your App.*.config files. It’ll look something like this:

  <ItemGroup>
    <None Include="App.Base.config">
      <DependentUpon>App.config</DependentUpon>
    </None>
    <None Include="App.Debug.Yaroslav.config">
      <DependentUpon>App.config</DependentUpon>
      <IsTransformFile>True</IsTransformFile>
    </None>
  </ItemGroup>
  
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug.Yaroslav|AnyCPU' ">
    <TransformOnBuild>True</TransformOnBuild>
    <TransformFile>App.Debug.Yaroslav.config</TransformFile>
    <TransformOriginalFile>App.Base.config</TransformOriginalFile>
  </PropertyGroup>
  

• Copy this section, replace all instances of App with Business, and adjust the filenames to match your Business.config and Business.Debug.Yaroslav.config.
• Save the .csproj file, then reload your project.

2. Verify File Properties #

Even if the project file is set up right, incorrect file properties can break transformations:

• Right-click Business.config → Properties.
  • Set Copy to Output Directory to "Copy if newer" or "Copy always".
  • Set Build Action to "Content".
• Do the same for Business.Debug.Yaroslav.config, but also ensure:
  • Build Action is set to "Content" or "None" (either works, but "Content" is safer for tracking).
  • The IsTransformFile flag is set to True (this should be handled by the .csproj edit above, but double-check in the properties if you don’t see it in the project file).

3. Check Your Transformation Syntax #

If the project setup looks good, the issue might be invalid XDT syntax in your Business.Debug.Yaroslav.config. Compare it directly to your working App.Debug.Yaroslav.config:

• Ensure every node you want to transform has the correct xdt:Transform and xdt:Locator attributes. For example, to replace an appSetting key:

  <appSettings>
    <add key="BusinessKey" value="DebugYaroslavValue" xdt:Transform="Replace" xdt:Locator="Match(key)" />
  </appSettings>
  

• Make sure the structure of your Business.Debug.Yaroslav.config matches the parent Business.config exactly—mismatched nodes will fail to apply.

4. Test the Build #

After making these changes:

• Switch to the Debug.Yaroslav configuration in Visual Studio.
• Clean your project (Build → Clean Solution).
• Rebuild the project (Build → Rebuild Solution).
• Navigate to your output directory (usually bin\Debug.Yaroslav) and open Business.config—it should now have the values from your Business.Debug.Yaroslav.config.

A quick sanity check: If you’re using a tool like SlowCheetah for config transformations (common in older VS versions), ensure you’ve added a transformation for Business.config just like you did for App.Base.config.

内容的提问来源于stack exchange，提问作者hellouworld