ios 保存图片到自己创建的相册

在QQ群里面看到有人问保存图片到自定义相册的办法：

直接上代码：

#import <Foundation/Foundation.h>
#import <AssetsLibrary/AssetsLibrary.h>

typedef void(^SaveImageCompletion)(NSError* error);

@interface ALAssetsLibrary(CustomPhotoAlbum)

-(void)saveImage:(UIImage*)image toAlbum:(NSString*)albumName withCompletionBlock:(SaveImageCompletion)completionBlock;
-(void)addAssetURL:(NSURL*)assetURL toAlbum:(NSString*)albumName withCompletionBlock:(SaveImageCompletion)completionBlock;

@end

#import "ALAssetsLibrary+CustomPhotoAlbum.h"

@implementation ALAssetsLibrary(CustomPhotoAlbum)

-(void)saveImage:(UIImage*)image toAlbum:(NSString*)albumName withCompletionBlock:(SaveImageCompletion)completionBlock
{
    //write the image data to the assets library (camera roll)
    [self writeImageToSavedPhotosAlbum:image.CGImage orientation:(ALAssetOrientation)image.imageOrientation
                        completionBlock:^(NSURL* assetURL, NSError* error) {

                          //error handling
                          if (error!=nil) {
                              completionBlock(error);
                              return;
                          }

                          //add the asset to the custom photo album
                          [self addAssetURL: assetURL
                                    toAlbum:albumName
                        withCompletionBlock:completionBlock];

                      }];
}

-(void)addAssetURL:(NSURL*)assetURL toAlbum:(NSString*)albumName withCompletionBlock:(SaveImageCompletion)completionBlock
{
    __block BOOL albumWasFound = NO;

    //search all photo albums in the library
    [self enumerateGroupsWithTypes:ALAssetsGroupAlbum
                        usingBlock:^(ALAssetsGroup *group, BOOL *stop) {

                            //compare the names of the albums
                            if ([albumName compare: [group valueForProperty:ALAssetsGroupPropertyName]]==NSOrderedSame) {

                                //target album is found
                                albumWasFound = YES;

                                //get a hold of the photo‘s asset instance
                                [self assetForURL: assetURL
                                      resultBlock:^(ALAsset *asset) {

                                          //add photo to the target album
                                          [group addAsset: asset];

                                          //run the completion block
                                          completionBlock(nil);

                                      } failureBlock: completionBlock];

                                //album was found, bail out of the method
                                return;
                            }

                            if (group==nil && albumWasFound==NO) {
                                //photo albums are over, target album does not exist, thus create it

                                __weak ALAssetsLibrary* weakSelf = self;

                                //create new assets album
                                [self addAssetsGroupAlbumWithName:albumName
                                                      resultBlock:^(ALAssetsGroup *group) {

                                                          //get the photo‘s instance
                                                          [weakSelf assetForURL: assetURL
                                                                        resultBlock:^(ALAsset *asset) {

                                                                            //add photo to the newly created album
                                                                            [group addAsset: asset];

                                                                            //call the completion block
                                                                            completionBlock(nil);

                                                                        } failureBlock: completionBlock];

                                                      } failureBlock: completionBlock];

                                //should be the last iteration anyway, but just in case
                                return;
                            }

                        } failureBlock: completionBlock];

}

@end

使用的时候只要调用：

-(void)saveImage:(UIImage*)image toAlbum:(NSString*)albumName withCompletionBlock:(SaveImageCompletion)completionBlock;即可……