/// 截圖
    ///
    /// - Parameters:
    ///   - view: view
    ///   - atFrame: rect
    func imageFromView(view : UIView,atFrame:CGRect) -> UIImage {
        UIGraphicsBeginImageContext(view.frame.size)
        let context = UIGraphicsGetCurrentContext()
        context?.saveGState()
        UIRectClip(atFrame)
        view.layer.render(in
 
: context!)
        let theImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return theImage!
    }