如何使用 NSJSONSerialization [英] How to use NSJSONSerialization

问题描述

我有一个 JSON 字符串(来自 PHP 的 json_encode()，看起来像这样:

I have a JSON string (from PHP's json_encode() that looks like this:

[{"id": "1", "name":"Aaa"}, {"id": "2", "name":"Bbb"}]

我想将其解析为我的 iPhone 应用程序的某种数据结构.我想对我来说最好的事情是拥有一个字典数组，所以数组中的第 0 个元素是一个字典，键为 "id" =>"1" 和 "name" =>啊".

I want to parse this into some sort of data structure for my iPhone app. I guess the best thing for me would be to have an array of dictionaries, so the 0th element in the array is a dictionary with keys "id" => "1" and "name" => "Aaa".

我不明白 NSJSONSerialization 如何存储数据.到目前为止，这是我的代码:

I do not understand how the NSJSONSerialization stores the data though. Here is my code so far:

NSError *e = nil;
NSDictionary *JSON = [NSJSONSerialization 
    JSONObjectWithData: data 
    options: NSJSONReadingMutableContainers 
    error: &e];

这只是我在另一个网站上看到的一个例子.我一直试图通过打印出元素的数量和类似的东西来读取 JSON 对象，但我总是得到 EXC_BAD_ACCESS.

This is just something I saw as an example on another website. I have been trying to get a read on the JSON object by printing out the number of elements and things like that, but I am always getting EXC_BAD_ACCESS.

如何使用NSJSONSerialization来解析上面的JSON，并变成我说的数据结构?

How do I use NSJSONSerialization to parse the JSON above, and turn it into the data structure I mentioned?

推荐答案

你的根 json 对象不是字典而是数组:

Your root json object is not a dictionary but an array:

[{"id": "1", "name":"Aaa"}, {"id": "2", "name":"Bbb"}]

这可能会让您清楚地了解如何处理它:

This might give you a clear picture of how to handle it:

NSError *e = nil;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: data options: NSJSONReadingMutableContainers error: &e];

if (!jsonArray) {
  NSLog(@"Error parsing JSON: %@", e);
} else {
   for(NSDictionary *item in jsonArray) {
      NSLog(@"Item: %@", item);
   }
}

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