主要代码下面2行

UIImage * saveimg=[self saveImage];

                                UIImageWriteToSavedPhotosAlbum(saveimg, self, @selector(savedPhotoImage:didFinishSavingWithError:contextInfo:), nil);

-(UIImage*)saveImage{

    UIGraphicsBeginImageContext(CGSizeMake(self.view.bounds.size.width, self.view.bounds.size.height - 20));//保存self.view上的内容

    [self.view.layer renderInContext:UIGraphicsGetCurrentContext()];

    UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return viewImage;

}

self.view可以替换成你想替换的任何控件