'NSInvalidArgumentException'，原因：'-[__ NSCFString objectAtIndex：]：无法识别的选择器已发送到实例

Question

Below is my code

   nameLabel.text=[[[dict_Details objectForKey:@"unknown_object"] objectAtIndex:0] objectForKey:@"UserFullName"];

here is my response

getUserReviewsResponse

{
"status_code" = 200;
"unknown_object" = "[{ID:227,ServiceProviderName:Dr.KarthikMendi,UserFullName:karthik,ReviewTemplateID:19,TotalScore:88.0,ServiceName:Doctor,Review:Very knowlegable doctor he understands the problem very well.,ServiceID:5,CommentsBySP:Thank you...,ServiceProviderID:0,CommentByAdmin:null,UserID:106,Status:true,CreatedDate:2016-05-06T18:30:08,Services:null,ServiceProviderTypes:null},{ID:168,ServiceProviderName:Dr.KarthikMendi,UserFullName:karthik,ReviewTemplateID:19,TotalScore:92.0,ServiceName:Doctor,Review:I am very impressed.  Very organized and professional.\\r\\nI always leave feeling taken care of and medical needs met. \\r\\nNeed more Dr\U00e2\U0080\U0099s like him!\\r\\nGreat!  He gave me sufficient time!\\r\\nVery friendly, informed and hospitable. \\r\\nVery nice \U00e2\U0080\U0093 didn\U00e2\U0080\U0099t feel like a number, but an actual person.,ServiceID:5,CommentsBySP:Thank you,ServiceProviderID:0,CommentByAdmin:null,UserID:84,Status:true,CreatedDate:2016-03-23T10:12:19.087,Services:null,ServiceProviderTypes:null}]";
}

Answer 1

The value for "unknown_object" is a string, but you are assuming it's a dictionary as you are calling objectForKey: on it. Hence the exception.

In general I would say that JSON is "broken" as it requires double-deserialization, which is less than useful.

Answer 2

Please check your json data in http://jsoneditoronline.org/ correct or not.

For example: Dr.KarthikMendi is string that include "Dr.KarthikMendi" (Double or single Quotation ).