iphone开发秘籍里面的捕捉屏幕截图代码
+ (UIImage *) imageFromView: (UIView *) theView

{

//Draw a view`s contents into an image context

UIGraphicsBeginImageContext(theView.frame.size);

CGContextRef context = UIGraphicsGetCurrentContext();

[theView.layer renderInContext:context];

UIGraphicsEndImageContext();

return theImage;

}

－－此函数要用到QuartzCore.framework框架


//获得某个范围内的屏幕图像
- (UIImage *)imageFromView: (UIView *) theView atFrame:(CGRect)r
{
UIGraphicsBeginImageContext(theView.frame.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSaveGState(context);
UIRectClip(r);
[theView.layer renderInContext:context];
UIImage *theImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

return theImage;//[self getImageAreaFromImage:theImage atFrame:r];
}