Question

使用以下代码。

+(void)getQuarterList:(NSString *)user_id
{
    if ([self checkInternet])
    {
        NSString *url=[NSString stringWithFormat:@"%@/api/v1/quarters.json",MainURL];
        AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
        NSDictionary *parameters = @{@"id":user_id};
      //  NSDictionary *parameters = @{};

        // NSDictionary *parameters = @{@"id":user_id,@"auth_token":auth_token};
        [manager POST:url parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject)
         {
             NSDictionary *dict=[[NSDictionary alloc]initWithDictionary:responseObject];
              //NSMutableArray *dict=[[NSMutableArray alloc]initWithArray:responseObject];
             NSLog(@"dict%@",dict);
             if ([dict valueForKey:@"Success"])
             {
                 NSNotification *notif1 = [NSNotification notificationWithName:@"quarterDetailsNotifier" object:[dict valueForKey:@"Success"]];
                 [[NSNotificationCenter defaultCenter] postNotification:notif1];
             }
             else if ([dict valueForKey:@"noData"])
             {
                 NSNotification *notif1 = [NSNotification notificationWithName:@"noDateNotifier" object:[dict valueForKey:@"Error"]];
                 [[NSNotificationCenter defaultCenter] postNotification:notif1];
             }

         } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
             NSLog(@"Error: %@", error);
             NSNotification *notif1 = [NSNotification notificationWithName:@"quarterDetailsFailNotifier" object:error];
             [[NSNotificationCenter defaultCenter] postNotification:notif1];
         }];
    }
    else
    {
        NSNotification *notif1 = [NSNotification notificationWithName:@"internetFailNotifier" object:nil];
        [[NSNotificationCenter defaultCenter] postNotification:notif1];
    }
}

我遇到以下错误

2014-05-20 15:39:33.610 TMLP[2770:a0b] The internet is working via WIFI.
2014-05-20 15:39:35.733 TMLP[2770:a0b] Error: Error Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be completed. (Cocoa error 3840.)" (JSON text did not start with array or object and option to allow fragments not set.) UserInfo=0x8e4a1a0 {NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set., NSUnderlyingError=0x8e65ca0 "Request failed: not found (404)"}
2014-05-20 15:39:35.734 TMLP[2770:a0b] -[NSError length]: unrecognized selector sent to instance 0x8e4a180

2014-05-20 15:39:35.737 TMLP[2770:a0b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSError length]: unrecognized selector sent to instance 0x8e4a180'

* 第一次抛出调用堆栈：如何解决这个错误

Answer 1

您将error作为NSNotification的对象发布。在通知处理程序中，您将其用作NSString或其他具有方法length的对象。

Answer 2

首先要做的事情您获取的JSON文本应始终以“[”或“{”开头，以便解析器识别它。你得到这个错误的原因显然是因为没有实现。我建议您通过在线提供的JSON验证器检查您的JSON文本我建议的第二件事是用于JSON序列化/反序列化

NSJSONSerialization

示例就像这样：

NSDictionary *jsonArray = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingAllowFragments error: &error];

options:NSJSONReadingAllowFragments可能会解决您正在解析的片段问题。如果这没有帮助，另一个选择是从获得的碎片字符串中提取出正确的JSON字符串。这意味着从字符串的开头和结尾消除额外的不需要的字符。

示例如下：

NSURL *url=[NSURL URLWithString:@"yourURL"];
    NSData *response = [NSData dataWithContentsOfURL:url];
    NSString *badjsonData = [NSString stringWithUTF8String:[response bytes]];
    NSString *goodJsonData = [badjsonData substringFromIndex:76];
    NSString *finaljsonData = [goodjsonData substringToIndex:[goodjsonData length]-9];
    NSData *goodData = [finaljsonData dataUsingEncoding:NSUTF8StringEncoding];
    NSError *error;
    NSDictionary *jsonArray = [NSJSONSerialization JSONObjectWithData:goodData options:NSJSONReadingAllowFragments error: &error];

如何解决ios 7中的json错误？

2 个答案: