获取系统相册里面的照片

-(void)getImgs{

dispatch_async(dispatch_get_main_queue(), ^{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

ALAssetsLibraryAccessFailureBlock failureblock = ^(NSError *myerror){
NSLog(@"相册访问失败 =%@", [myerror localizedDescription]);
if ([myerror.localizedDescription rangeOfString:@"Global denied access"].location!=NSNotFound) {
NSLog(@"无法访问相册.请在'设置->定位服务'设置为打开状态.");
}else{
NSLog(@"相册访问失败.");
}
};

ALAssetsGroupEnumerationResultsBlock groupEnumerAtion = ^(ALAsset *result, NSUInteger index, BOOL *stop){
if (result!=NULL) {

if ([[result valueForProperty:ALAssetPropertyType] isEqualToString:ALAssetTypePhoto]) {

NSString *urlstr=[NSString stringWithFormat:@"%@",result.defaultRepresentation.url];//图片的url

NSLog(@"urlstr = %@",urlstr);
UIImage *image = [UIImage imageWithCGImage:[result thumbnail]];
[arr addObject:image];
/*result.defaultRepresentation.fullScreenImage//图片的大图
result.thumbnail //图片的缩略图小图
// NSRange range1=[urlstr rangeOfString:@"id="];
// NSString *resultName=[urlstr substringFromIndex:range1.location+3];
// resultName=[resultName stringByReplacingOccurrencesOfString:@"&ext=" withString:@"."];//格式demo:123456.png
*/
[self._dataArray addObject:urlstr];
}
}

};

ALAssetsLibraryGroupsEnumerationResultsBlock
libraryGroupsEnumeration = ^(ALAssetsGroup* group, BOOL* stop){

if (group == nil)
{

}

if (group!=nil) {
NSString *g=[NSString stringWithFormat:@"%@",group];//获取相簿的组
NSLog(@"gg:%@",g);//gg:ALAssetsGroup - Name:Camera Roll, Type:Saved Photos, Assets count:71

NSString *g1=[g substringFromIndex:16 ] ;
NSArray *arr=[[NSArray alloc] init];
arr=[g1 componentsSeparatedByString:@","];
NSString *g2=[[arr objectAtIndex:0] substringFromIndex:5];
if ([g2 isEqualToString:@"Camera Roll"]) {
g2=@"相机胶卷";
}
NSString *groupName=g2;//组的name

[group enumerateAssetsUsingBlock:groupEnumerAtion];
}

};

ALAssetsLibrary* library = [[ALAssetsLibrary alloc] init];
[library enumerateGroupsWithTypes:ALAssetsGroupAll
usingBlock:libraryGroupsEnumeration
failureBlock:failureblock];
[library release];
[pool release];
});

NSLog(@"dataarray = %d",_dataArray.count);

}

//------------------------根据图片的url反取图片－－－－－/
/*
ALAssetsLibrary *assetLibrary=[[ALAssetsLibrary alloc] init];
NSURL *url=[NSURL URLWithString:urlStr];
[assetLibrary assetForURL:url resultBlock:^(ALAsset *asset) {
UIImage *image=[UIImage imageWithCGImage:asset.thumbnail];
cellImageView.image=image;

}failureBlock:^(NSError *error) {
NSLog(@"error=%@",error);
}
];
*///－－－－－－－－－－－－－－－－－－－－－