iOS 获取屏幕某个区域的截图

-(void)fullScreenshots{

    

    UIWindow *screenWindow = [[UIApplicationsharedApplication]
keyWindow];

    

    UIGraphicsBeginImageContext(screenWindow.frame.size);//全屏截图，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;

   
//你需要的区域起点,宽,高;

    

    CGRect rect1 =CGRectMake(originX , originy , width , height);

    

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

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

    snapImg.backgroundColor = [UIColorredColor];

    snapImg.image = imgeee;

    [self.viewaddSubview:snapImg];

}

或者：

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

    

    

    UIImage *image = [self
snapshot:_sampleView];

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

    snapImg.layer.borderWidth =
1;

    

    snapImg.image = image;

    [self.view
addSubview:snapImg];

    

}

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

    

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

    [view drawViewHierarchyInRect:view.bounds
afterScreenUpdates:YES];

    

    UIImage *image =
UIGraphicsGetImageFromCurrentImageContext();

    

    UIGraphicsEndImageContext();

    

    return image;

    

}