Question

我将应用程序代码移动到MVC模型，因此我创建了一种从API检索某些数据的方法。

+ (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，我希望将jsonArray作为此方法的一部分返回。但是，由于AFHTTPRequestOperation是异步的，我不知道如何解决此问题，仍然可以在应用中的任何位置调用[Data loadFromFeed];。我怎么能这样做？

Answer 1

你可以将名为success和failure的两个块传递给loadFromFeed，然后从setCompletionBlockWithSuccess成功和失败块中调用两个块，将jsonArray传递给成功块：

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)
}];];

从AFHTTPRequestOperation返回数据？

1 个答案: