Afnetworking等待网络请求，继续同步操作

title: AFNetworking等待网络请求，继续同步操作 date: 2016-11-09 23:04 tags: iOS category: 技术笔记 —

在发出网络请求后，需要拿到网络返回的数据才能继续后续操作，这时可以用 ` dispatch_semaphore_wait() `

- (id)sendForUrl:(NSURL *)url {
    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];

    manager.completionQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0); <!--more-->        dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);

    __block id response;

    [manager GET:url.absoluteString parameters:nil success: ^(AFHTTPRequestOperation *operation, id responseObject) {
        response = responseObject;
        NSLog(@"JSON: %@", responseObject);
        dispatch_semaphore_signal(semaphore);
    } failure: ^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Error: %@", error);
        dispatch_semaphore_signal(semaphore);
    }];

    dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);

    return response;
}

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