iOS常用到的圖片功能:截取當前螢幕/選擇本地圖片/圖片壓縮

iOS常用到的圖片功能:截取當前螢幕/選擇本地圖片/圖片壓縮

截取當前螢幕

UIGraphicsBeginImageContextWithOptions(CGSizeMake(CGRectGetWidth(self.superview.frame), CGRectGetHeight(self.superview.frame)), NO, 1);[self.superview drawViewHierarchyInRect:CGRectMake(0, 0, CGRectGetWidth(self.superview.frame), CGRectGetHeight(self.superview.frame)) afterScreenUpdates:NO];UIImage *snapshot = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext();

選擇本地圖片

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];imagePicker.delegate = self;imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical;//        imagePicker.allowsEditing = YES;[self presentViewController:imagePicker animated:YES completion:nil];

圖片壓縮

- (UIImage*)presentImageWithBigImg:(UIImage*)image{    NSData *imageData = UIImageJPEGRepresentation(image,0.001);    UIImage *newImg = [UIImage imageWithData:imageData];    if (newImg) {        return newImg;    }else{        return image;    }}