从AFHTTPRequestOperation返回数据？

Question

我正在将我的应用程序代码转移到MVC模型，所以我创建了一个方法来从API中检索一些数据。

+ (NSMutableArray *)loadFromFeed {
    NSString *feed = @"https://api.test.com";

    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:feedUrl]];

    request = [mutableRequest copy];

    AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
    operation.responseSerializer = [JSONResponseSerializerWithData serializer];

    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
        NSArray *jsonArray = (NSArray *)[responseObject objectForKey:@"items"];
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        CLS_LOG(@"Error");
    }];
}

现在，理想情况下，我希望返回jsonArray作为此方法的一部分。但是，由于AFHTTPRequestOperation是异步的，我不知道如何解决这个问题，并且仍然能够在应用程序中的任何地方调用[Data loadFromFeed];。我该怎么做？

Answer 1

您可以将名为“成功和失败”的两个块传递给loadFromFeed，然后从setCompletionBlockWithSuccess成功和失败块调用两个块，将jsonArray传递到成功块：

typedef void (^Success)(id data);
typedef void (^Failure)(NSError *error);

- (void)loadFromFeed:(Success)success failure:(Failure)failure;


[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
    NSArray *jsonArray = (NSArray *)[responseObject objectForKey:@"items"];
    success?success(jsonArray):nil;
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    failure?failure(error):nil;
}];

然后以这种方式使用：

[Data loadFromFeed:^(id data) {
    NSLog(@"%@",data)
} failure:^(NSError *error) {
    NSLog(@"%@",error)
}];];