-(void)fullScreenshots{

UIWindow *screenWindow = [[UIApplicationsharedApplication] keyWindow];

UIGraphicsBeginImageContext(screenWindow.frame.size);//全屏截圖，包括window

    [screenWindow.layerrenderInContext:UIGraphicsGetCurrentContext()];

UIImage *viewImage =UIGraphicsGetImageFromCurrentImageContext

UIGraphicsEndImageContext();

//    UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

float originX =_sampleView.frame.origin.x;

float originy =_sampleView.frame.origin.y;

float width =_sampleView.frame.size.width;

float height =_sampleView.frame.size.height;

//你需要的區域起點,寬,高;

CGRect

UIImage * imgeee = [UIImageimageWithCGImage:CGImageCreateWithImageInRect([viewImageCGImage], rect1)];

UIImageView *snapImg = [[UIImageViewalloc] initWithFrame:CGRectMake(0,200, 170,170)];

    snapImg.backgroundColor = [UIColorredColor];

    snapImg.

    [self.viewaddSubview:snapImg];

}

或者：

- (void)snapAction:(UIButton *)btn {

UIImage *image = [selfsnapshot:_sampleView];

UIImageView *snapImg = [[UIImageViewalloc] initWithFrame:CGRectMake(0, 200, 170, 170)];

    snapImg.layer.borderWidth = 1;

    snapImg.image = image;

    [self.viewaddSubview:snapImg];

}

- (UIImage *)snapshot:(UIView *)view {

UIGraphicsBeginImageContextWithOptions(view.bounds.size,YES,0);

    [view drawViewHierarchyInRect:view.boundsafterScreenUpdates:YES];

UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

return image;

}