view转换image

-(UIImage *)getImageFromView:(UIView *)theView

{

    //UIGraphicsBeginImageContext(theView.bounds.size);

    UIGraphicsBeginImageContextWithOptions(theView.bounds.size, YES, theView.layer.contentsScale);

    [theView.layer renderInContext:UIGraphicsGetCurrentContext()];

    UIImage *image=UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return image;

}