使用方法：
SHFILEOPSTRUCT DirRemove;
DirRemove.fFlags = FOF_NOCONFIRMATION;
DirRemove.hNameMappings = NULL;
DirRemove.hwnd = NULL;
DirRemove.lpszProgressTitle = NULL;
DirRemove.pFrom = "D:\\MyBlog";
DirRemove.pTo = NULL;
DirRemove.wFunc = FO_DELETE;
SHFileOperation(&DirRemove);
注意点：
FileOp.pFrom这个参数,它使用的字符串一定是要'\0'结尾的,
"D:\\MyBlog"这个字符串默认的结束字符就是'\0',
如果像下面这样写的话就会出错:
std::string delPath = "D:\\MyBlog";
FileOp.pFrom = delPath.c_str();
string变量转化为CHAR[] 再使用