ios批量保存图片到本地相册

这里总结两种保存图片到相册的方法。

1.UIImageWriteToSavedPhotosAlbum()保存到相册，该方法图片会被压缩。
2.使用Photos框架中的PHPhotoLibrary来存储图片

1.UIImageWriteToSavedPhotosAlbum()存储图片

- (void)saveImages:(NSArray *)imageArrs {
    for (int i = 0; i <imageArrs.count; i++) {
        [self.downloadImageArrs addObject:imageArrs[i]];
    }
    PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
    // 2.判断用户的授权状态
    if (status == PHAuthorizationStatusNotDetermined) {
        // 如果状态是不确定的话,block中的内容会等到授权完成再调用
        [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
            // 授权完成就会调用
            if (status == PHAuthorizationStatusAuthorized) {
            //调用存储图片的方法
                [self CWWSavePhotos];
            }
        }];
        //如果允许访问
    } else if (status == PHAuthorizationStatusAuthorized) {
        //调用存储图片的方法
        [self CWWSavePhotos];
        //如果权限是拒绝
    } else {
        //弹出一个页面提示用户去打开授权
        [MBProgressHUD showInWindowMessage:@"进入设置打开允许访问相册开关"];
    }
//储图片的方法
- (void)CWWSavePhotos {
    if (self.downloadImageArrs.count > 0) {
        [self saveimage:[self.downloadImageArrs objectAtIndex:0]];
    }
}
#pragma mark - 保存图片的方法
- (void)saveimage:(NSString *)imageUrl {
    NSURL *imgUrl = [NSURL URLWithString:imageUrl];
    [[SDWebImageDownloader sharedDownloader] downloadImageWithURL:imgUrl completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished) {
        if (image) {
            UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
            //清除sd缓存，防止图片被sdwebimage缓存
            [[SDImageCache sharedImageCache] clearDiskOnCompletion:nil];
            [[SDImageCache sharedImageCache] clearMemory];
        }
    }];
}
- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo {
    if (error) {
        [MBProgressHUD showInWindowMessage:@">_< 保存失败"];
    } else {
      
        [self.downloadImageArrs removeObjectAtIndex:0];
        if (self.downloadImageArrs.count==0) {
          [MBProgressHUD showInWindowMessage:@"^_^ 保存成功"];
        }
    }
    [self CWWSavePhotos];
}

2.使用Photos框架中的PHPhotoLibrary来存储图片

- (void)saveImages:(NSArray *)imageArrs {
    for (int i = 0; i <imageArrs.count; i++) {
        [self.downloadImageArrs addObject:imageArrs[i]];
    }
    PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
    // 2.判断用户的授权状态
    if (status == PHAuthorizationStatusNotDetermined) {
        // 如果状态是不确定的话,block中的内容会等到授权完成再调用
        [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
            // 授权完成就会调用
            if (status == PHAuthorizationStatusAuthorized) {
            //调用存储图片的方法
                [self CWWSavePhotos];
            }
        }];
        //如果允许访问
    } else if (status == PHAuthorizationStatusAuthorized) {
        //调用存储图片的方法
        [self CWWSavePhotos];
        //如果权限是拒绝
    } else {
        //弹出一个页面提示用户去打开授权
        [MBProgressHUD showInWindowMessage:@"进入设置打开允许访问相册开关"];
    }
}
//储图片的方法
- (void)CWWSavePhotos {
    if (self.downloadImageArrs.count > 0) {
       [self saveToPhoto:[self.downloadImageArrs objectAtIndex:0]];
    }
}
#pragma mark - 获取在图库中是否已经创建该App的相册

//该方法的作用,获取系统中所有的相册,进行遍历,若是已有相册,返回该相册,若是没有返回nil,参数为需要创建  的相册名称
- (PHAssetCollection *)fetchAssetColletion:(NSString *)albumTitle {
    // 获取所有的相册
    PHFetchResult *result = [PHAssetCollection           fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
    //遍历相册数组,是否已创建该相册
    for (PHAssetCollection *assetCollection in result) {
        if ([assetCollection.localizedTitle isEqualToString:albumTitle]) {
            
            return assetCollection;
            
        }
    }
    return nil;
}
#pragma mark - 保存图片的方法
- (void)saveToPhoto:(NSString *)imageUrl{
    
    NSURL *imgUrl = [NSURL URLWithString:imageUrl];
    [[SDWebImageDownloader sharedDownloader] downloadImageWithURL:imgUrl completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished)  {
        
        NSLog(@"dataLen:%lu",data.length);
        if (finished)
        {
            UIImage * imgsave = image;
            [[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
                // 调用判断是否已有该名称相册
                NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
                //以项目名字命名相册
                NSString *app_Name = [infoDictionary objectForKey:@"CFBundleDisplayName"];
                PHAssetCollection *assetCollection = [self fetchAssetColletion:app_Name];
                //创建一个操作图库的对象
                PHAssetCollectionChangeRequest *assetCollectionChangeRequest;
                if (assetCollection) {
                    // 已有相册
                    assetCollectionChangeRequest = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:assetCollection];
                } else {
                    // 1.创建自定义相册
                    assetCollectionChangeRequest = [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:app_Name];
                }
                // 2.保存你需要保存的图片到系统相册
                PHAssetChangeRequest *assetChangeRequest = [PHAssetChangeRequest creationRequestForAssetFromImage:imgsave];
                // 3.把创建好图片添加到自己相册(ps:想保存到系统相册，就注释掉下边一行代码就ok)
                //这里使用了占位图片,为什么使用占位图片呢
                //这个block是异步执行的,使用占位图片先为图片分配一个内存,等到有图片的时候,再对内存进行赋值
                PHObjectPlaceholder *placeholder = [assetChangeRequest placeholderForCreatedAsset];
                [assetCollectionChangeRequest addAssets:@[placeholder]];
            } completionHandler:^(BOOL success, NSError * _Nullable error) {
                if (error) {
                    // NSLog(@"保存失败");
                } else {
                    //NSLog(@"保存成功");
                    [self.downloadImageArrs removeObjectAtIndex:0];
                }
                [self CWWSavePhotos];
            }];
        }
    }];
}