激活灰显按钮

long Style;
Style = ::GetWindowLong(hWnd,GWL_STYLE); //获得Style值
Style ^= WS_DISABLED; //去掉WS_DISABLED 你也可以用|=把属性加回去
::SetWindowLong(hWnd,GWL_STYLE,Style); //设置回去
::SetWindowPos(hWnd,0,0,0,0,SWP_FRAMECHANGED | SWP_NOSIZE | SWP_NOZORDER | SWP_NOMOVE);