nuget问题，程序包源找不到，安装不上

 替换这里的文件内容：

C:\Users\yansc\AppData\Roaming\NuGet\NuGet.Config

就有了

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <!-- Define the package sources, nuget.org and contoso.com. -->
  <!-- `clear` ensures no additional sources are inherited from another config file. -->
  <packageSources>
    <clear />
    <!-- `key` can be any identifier for your source. -->
    <add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
    <add key="contoso.com" value="https://contoso.com/packages/" />
  </packageSources>
  
  <!-- Define mappings by adding package patterns beneath the target source. -->
  <!-- Contoso.* packages and NuGet.Common will be restored from contoso.com,
       everything else from nuget.org. -->
  <packageSourceMapping>
    <!-- key value for <packageSource> should match key values from <packageSources> element -->
    <packageSource key="nuget.org">
      <package pattern="*" />
    </packageSource>
    <packageSource key="contoso.com">
      <package pattern="Contoso.*" />
      <package pattern="NuGet.Common" />
    </packageSource>
  </packageSourceMapping>
  <config> 
    <add key="globalPackagesFolder" value="D:\nuget\packages" />
</config>
</configuration>

 

包源映射这样：