iPhone：使用SBJSON Parser进行JSON解析会出错

Question

Hi I am making an iPhone app where in I am getting response from webservice in JSON format. I am using SBJSON Parser for parsing my data.

I am getting an error while I try parsing the data.

I have reffered to following links but none of them did help:

How to handle '[<__NSCFString 0x2f1730> valueForUndefinedKey:]: this class is not key value coding-compliant for the key $oid' error

NSCFString 0x2749a0 valueForUndefinedKey this class is not key value coding-compliant for the key data

What could be wrong?

Any help is appreciated.

Code:

 NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL: [NSURL URLWithString: @"<MyWebserviceURL>"]];

    /* Following function is used to convert and concate json string with url and create query string to exicute to the server.*/
    [request addValue: @"application/json; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
    [request addValue: @"application/json; charset=utf-8" forHTTPHeaderField:@"Accept"];
    NSString *msgLength = [NSString stringWithFormat:@"%d", [soapMessage length]];
    [request addValue: msgLength forHTTPHeaderField:@"Content-Length"];
    [request setHTTPMethod:@"POST"];
    [request setHTTPBody: [soapMessage dataUsingEncoding:NSUTF8StringEncoding]];

    NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse: nil error: nil];

    /* This string will convert all the data format to string format and store it.*/
    NSString *myString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
    NSLog(@"getresponse:%@",myString);
    /* This string will used get json value and split the value starting from "d".*/
    //NSDictionary *d = [[myString JSONValue] objectForKey:@"d"];
    NSLog(@"[myString JSONValue]: %@",[[myString JSONValue] class]);
    NSDictionary *d = [[myString JSONValue]  valueForKey:@"d"];  //  <----- ERROR IS SHOWN HERE

Console Log shows:

    getresponse:{"d":{"__type":"<CompanyName>.<AppName>.BusinessLogic.RegisterWebservice","ErrorObject":{"__type":"<CompanyName>.<AppName>.BusinessLogic.Error","ErrorMessage":"","ErrorCode":0},"AttendeeCredentials":{"__type":"<CompanyName>.<AppName>.BusinessLogic.AttendeeCredential","UserID":"abcd","Password":"abcd"},"ServerDeviceSN":"PKKPAPPKAPPKAPK090"}}
    [myString JSONValue]: __NSCFString

    *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<__NSCFString 0xc384f30> valueForUndefinedKey:]: this class is not key value coding-compliant for the key d.'
*** First throw call stack:
(0x2eaa012 0x2b1ae7e 0x2f32fb1 0x13aa5ed 0x13168db 0x131688d 0xf6aef 0xf64b9 0xfecef 0xfe834 0x13490d5 0x1349034 0x950d8ed9 0x950dc6de)
libc++abi.dylib: terminate called throwing an exception

Answer 1

You need to use the NSDictionary method -objectForKey: rather than the Key-Value-Coding method -valueForKey: . These are not (always) interchangeable.