IOS 判断相册是否允许访问

-(void)savedLibrayImage:(UIImage *)image
{
ALAssetsLibrary *library = [[ALAssetsLibrary alloc]init];
[library writeImageToSavedPhotosAlbum:image.CGImage orientation:image.imageOrientation completionBlock:^(NSURL *asSetUrl,NSError *error){
if (error) {
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"存储失败"
message:@"请打开 设置-隐私-照片 来进行设置"
delegate:nil
cancelButtonTitle:@"确定"
otherButtonTitles:nil, nil];
[alert show];
[alert release];
}else{
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"存储成功"
message:nil
delegate:nil
cancelButtonTitle:@"确定"
otherButtonTitles:nil, nil];
[alert show];
[alert release];
}

}];
}