//截屏 static int i=0; -(IBAction)screenShot:(id)sender{      UIGraphicsBeginImageContextWithOptions(CGSizeMake(640, 960), YES, 0);   [[self.window layer] renderInContext:UIGraphicsGetCurrentContext()];   UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();   UIGraphicsEndImageContext();   CGImageRef imageRef = viewImage.CGImage;   CGRect rect =CGRectMake(166, 211, 426, 320);//這里可以設置想要截圖的區域   CGImageRef imageRefRect =CGImageCreateWithImageInRect(imageRef, rect);   UIImage *sendImage = [[UIImage alloc] initWithCGImage:imageRefRect];   UIImageWriteToSavedPhotosAlbum(sendImage, nil, nil, nil);//保存圖片到照片庫   NSData *imageViewData = UIImagePNGRepresentation(sendImage);      NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);   NSString *documentsDirectory = [paths objectAtIndex:0];   NSString *pictureName= [NSString stringWithFormat:@"screenShow_%d.png",i];   NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:pictureName];   NSLog(@"%@", savedImagePath);   [imageViewData writeToFile:savedImagePath atomically:YES];//保存照片到沙盒目錄   CGImageRelease(imageRefRect);   i++; }