Every now and then our source control engine indicates that the ProductVersion in a .csproj file has changed. We're using VS2008 SP1.
Looking through the codebase I can see two versions reported:
<ProductVersion>9.0.30729</ProductVersion>
and
<ProductVersion>9.0.21022</ProductVersion>
Does anyone know why and when Visual Studio decides to change this setting, and to what these two version numbers refer?
That's the version of Visual Studio used to load the .csproj, so it knows what capabilities the project might contain (if new versions of VS change the format of the proj file).
It will change when the project is loaded - VS is silently doing a minor 'upgrade' to the project file.
Look at a VS2005 proj file, you'll see the ProjectVersion is set to 8.0.xxx
来源：https://stackoverflow.com/questions/1299492/what-controls-the-productversion-setting-in-csproj-files