1、图片的压缩

封装类方法

    + (UIImage*)imageWithImageSimple:(UIImage*)image scaledToSize:(CGSize)newSize        {            // Create a graphics image context            UIGraphicsBeginImageContext(newSize);                        // Tell the old image to draw in this new context, with the desired            // new size            [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];                        // Get the new image from the context            UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();                        // End the context            UIGraphicsEndImageContext();                        // Return the new image.            return newImage;        }  

    //屏幕截图并压缩            UIImage *snapshot =  [UIImage imageWithCGImage:[AppDelegate screenShots].CGImage scale:1 orientation:UIImageOrientationLeft];            _updataImg =[AppDelegate imageWithImageSimple:snapshot scaledToSize:CGSizeMake(snapshot.size.width/3, snapshot.size.height/3)];  

2、保存View为内容Img

    -(void)savetoLocal        {            _moreVC.hidden =YES;            UIImage * saveimg=[self saveImage];             UIImageWriteToSavedPhotosAlbum(saveimg, self, @selector(imageSavedToPhotosAlbum: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;        }                - (void)imageSavedToPhotosAlbum:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(voidvoid *)contextInfo        {            NSString *message = @"呵呵";            if (!error) {                message = @"成功保存到相册";            }else            {                message = [error description];            }            NSLog(@"message is %@",message);        }