caffe CUDA 9.0.targets(532,9): error : The CUDA Toolkit v9.0 directory '' does not exist.

1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V120\BuildCustomizations\CUDA 9.0.targets(532,9): error : The CUDA Toolkit v9.0 directory '' does not exist.  Please verify the CUDA Toolkit is installed properly or define the CudaToolkitDir property to resolve this error.
解決方法：

右鍵 libcaffe 工程屬性，找到 CUDA C/C++

設置 CUDA Tookit Custom Dir的值，指定CUDA的安裝目錄即可