JSON from NSDictionary

Question

我想为APNs消息创建一个JSON兼容的字典，看起来像这样:

{
      "aps" : {
        "alert": "new push"
      }
}

实际上我可以这样写:

  {
        aps = {
            alert = "new push";
        };
    }

这是我的实际代码:

    NSString *content = [NSString stringWithFormat:@"new push."];
    self.dict1 = @{ @"alert": content} ;
    NSMutableDictionary *newPush = [NSMutableDictionary dictionary];
    [newPush setObject:self.dict1 forKey:@"aps"];

有人可以解释我，我做错了什么?如何将其转换为正确的格式?

---

更新

 NSDictionary *dict = @{ @"aps" : @{ @"alert" : content } };

//create the json
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dict
                                                   options:NSJSONWritingPrettyPrinted
                                                     error:&error];
NSString* jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];

我从控制台得到了这个建议:There was an error sending the data to the origin. Be sure you didn't try to send non-object or non-JSON data.

Answer 1

你可以直接做

NSDictionary *dict = @{
    @"aps" : @{ @"alert" : @"new push" }
};

(与您在前两个代码示例中编写的方式非常相似)。

然后使用NSJSONSerialization创建格式化的JSON

Answer 2

使用NSJSONSerialization将Dictionary或NSArray转换为json对象

...
NSError *error; 
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:newPush 
                                        options:NSJSONWritingPrettyPrinted 
                                        error:&error];
...