打开项目的vcxproj文件

    <ClCompile Include="generatedfiles\Debug\moc_XXXX">
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">false</ExcludedFromBuild>
    </ClCompile>

ClCompile 项中的ExcludedFromBuild

需要编译的为false，不需要编译的为true

比如上面

      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">false</ExcludedFromBuild>

Release不编译，Debug编译

LNK2001    无法解析的外部符号 "public: virtual int __thiscall XXXXXXXX::qt_metacall(enum QMetaObject::Call,int,void * *)

同样的这个情况也可能是moc文件没编进去检查一下是否被排除了

1>C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\VC\VCTargets\Microsoft.CppBuild.targets(937,5): warning MSB8027: 名为 moc_Timer.cpp 的两个或更多文件将生成到同一位置的输出。这会导致错误的生成结果。   调用的文件是 generatedfiles\Debug\moc_XXXXXX.cpp, generatedfiles\Release\moc_XXXXX.cpp。

这个警告是因为
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>

2个都为true