将 NSString 转换为 NSDictionary

Posted 2023-03-11

【中文标题】将 NSString 转换为 NSDictionary

【英文标题】：Convert NSString in to NSDictionary

【发布时间】：2018-02-19 06:00:55

【问题描述】：

我正在使用 JSON POST 方法，我的代码是

[_urlReq setValue:@"application/x-www-form-urlencoded; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
[_urlReq setHTTPMethod:@"POST"];
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:@"%lu", (unsigned long) [postData length]];
[_urlReq setValue:postLength forHTTPHeaderField:@"Content-Length"];
[_urlReq setHTTPBody:postData];
_dataTask = [_urlSession dataTaskWithRequest:_urlReq  completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) 

if (!(data == nil)) 

我正在将响应数据转换为字符串格式

NSString* myString = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];// NSUTF8StringEncoding
NSLog(@"myString :%@", myString);

OutPut:

myString :"Response":"status":"SUCCESS","error_code":"0","message":"message","Array":["name" => "VVV","name" => "CHE","ac" => "5a8805a","email" =>"vvv","line1" =>"","line2" =>"","no" =>"","street" =>"","pin_code" =>"","state_id" =>"0","district_name" =>"0"]

//Convert string into Dic
NSData *data1 = [myString dataUsingEncoding: NSUTF8StringEncoding];
id json = [NSJSONSerialization JSONObjectWithData:data1 options:0 error:nil];
NSLog(@"json : %@", json);
NSLog(@"Response : %@",[json objectForKey:@"Response"]);

//Second approach to convert string to dic
NSError *err = nil;
NSArray *array = [NSJSONSerialization JSONObjectWithData:[myString dataUsingEncoding:NSUTF8StringEncoding] options:NSJSONReadingMutableContainers error:&err];
NSLog(@"array :%@", array);
NSDictionary *dictionary = [array objectAtIndex:0];
NSLog(@"dictionary : %@", dictionary);
NSString *test = [dictionary objectForKey:@"Response"];
NSLog(@"Test is %@",test);                               

我不知道这里有什么问题......

【问题讨论】：

你检查错误err了吗？

我从服务器收到这样的响应 myString :"Response":"status":"SUCCESS","error_code":"0","message":"message","数组":["name" => "VVV","name" => "CHE","ac" => "5a8805a","email" =>"vvv","line1" =>""," line2" =>"","no" =>"","street" =>"","pin_code" =>"","state_id" =>"0","district_name" =>"0"] 。但是当从 String 转换为 Dic 时没有得到任何错误

NSArray *array = [NSJSONSerialization JSONObjectWithData:[myString dataUsingEncoding:NSUTF8StringEncoding] 选项：NSJSONReadingMutableContainers 错误：&err]; NSLog(@"array :%@", array); ?? Y 转换 NSArray ??

您的 json 字符串无效。请提供一个有效的 json 字符串。

@McDonal_1 我已经这样做了 //Second approach to convert string to dic NSError *err = nil; NSArray *array = [NSJSONSerialization JSONObjectWithData:[myString dataUsingEncoding:NSUTF8StringEncoding] 选项：NSJSONReadingMutableContainers 错误：&err]; NSLog(@"array :%@", array);

【参考方案1】：

你的 JSON 格式是以字典开头的。

而不是，

NSArray *array = [NSJSONSerialization JSONObjectWithData:[myString dataUsingEncoding:NSUTF8StringEncoding] options:NSJSONReadingMutableContainers error:&err];
NSLog(@"array :%@", array);

替换它并尝试

NSDictionary *jSonDict = [NSJSONSerialization JSONObjectWithData:[myString dataUsingEncoding:NSUTF8StringEncoding] options:NSJSONReadingMutableContainers error:&err]; 

第二次尝试：

NSDictionary *jSonDict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:&err];

有关更多信息，如何验证 JSON，请使用此链接 enter link description here

您的 JSON：

【讨论】：

我得到 Null NSLog ("%@", jSonDict);

您可以直接将数据转换为字典。

@ McDonal_11 不，当我直接从数据转换为 dic 时，它会变为空。当我仅从数据转换为字符串时，我收到此响应 "Response":"status":"SUCCESS","error_code":"0","message":"message","Array":[ "name" => "VVV","name" => "CHE","ac" => "5a8805a","email" =>"vvv","line1" =>"","line2" =>" ","no" =>"","street" =>"","pin_code" =>"","state_id" =>"0","district_name" =>"0"] 为什么我不这样做不知道

在邮递员中，我收到这样的响应 "Response":"status":"SUCCESS","error_code":"0","message":"message","Array ":["name" => "VVV","name" => "CHE","ac" => "5a8805a","email" =>"vvv","line1" =>"","line2 " =>"","door_no" =>"","street" =>"","pin_code" =>"","state_id" =>"0","district_name" =>"0"]

你可以发截图吗？如果可能的话？

【参考方案2】：

用这个替换 JSON 响应字符串

"Response":"status":"SUCCESS","error_code":"0","message":"message","Array":["name" : "VVV","name" : "CHE","ac" : "5a8805a","email" : "vvv","line1" : "","line2" : "","no" : "","street" : "","pin_code" : "","state_id" : "0","district_name" : "0"]

【参考方案3】：

您的 json 字符串不正确。请检查我的演示 json 字符串。

试试这个

let myString :String = "\"Response\":\"status\":\"SUCCESS\",\"error_code\":\"0\",\"message\":\"message\",\"Array\":[\"name\" : \"VVV\",\"name\" : \"CHE\",\"ac\" : \"5a8805a\",\"email\" :\"vvv\",\"line1\" :\"\",\"line2\" :\"\",\"no\" :\"\",\"street\" :\"\",\"pin_code\" :\"\",\"state_id\" :\"0\",\"district_name\" :\"0\"]"

    if let data = myString.data(using: .utf8)
        do
            let json = try JSONSerialization.jsonObject(with: data, options: .init(rawValue: 0));
            print(json)
        catch

        

    

输出

    Response =     
        Array =         (
                        
                ac = 5a8805a;
                "district_name" = 0;
                email = vvv;
                line1 = "";
                line2 = "";
                name = VVV;
                no = "";
                "pin_code" = "";
                "state_id" = 0;
                street = "";
            
        );
        "error_code" = 0;
        message = message;
        status = SUCCESS;
    ;