个人记录---截屏方法

方法一：

- (UIImage*)capture
{

UIGraphicsBeginImageContextWithOptions(self.frame.size,NO, [UIScreenmainScreen].scale);

[selfdrawViewHierarchyInRect:CGRectMake(0,0,self.frame.size.width,self.frame.size.height)afterScreenUpdates:YES];

UIImage*image =UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

returnimage;

}

方法二：

- (UIImage*)getImage {

UIGraphicsBeginImageContextWithOptions(CGSizeMake(self.frame.size.width,self.frame.size.height),NO,1.0);//NO，YES控制是否透明

[self.layerrenderInContext:UIGraphicsGetCurrentContext()];

UIImage*image =UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

//生成后的image

return[selfgetImageFromImage:image];

}
//根据给定得图片，从其指定区域截取一张新得图片

-(UIImage*)getImageFromImage:(UIImage*)bigImage

{

//大图bigImage

//定义myImageRect，截图的区域

CGRectmyImageRect =CGRectMake(floatIntervalW+1,floatY+1,floatW-2,floatW-2);

CGImageRefimageRef = bigImage.CGImage;

CGImageRefsubImageRef =CGImageCreateWithImageInRect(imageRef, myImageRect);

CGSizesize;

size.width=floatW-2;

size.height=floatW-2;

UIGraphicsBeginImageContext(size);

CGContextRefcontext =UIGraphicsGetCurrentContext();

CGContextDrawImage(context, myImageRect, subImageRef);

UIImage* smallImage = [UIImageimageWithCGImage:subImageRef];

UIGraphicsEndImageContext();

returnsmallImage;

}