Objective-C - “success” not equal to “success”

Question

The basic gist: I've got some JSON coming back from a webservice to validate a login; that part works. I'm pulling values out of the array into an NSDictionary; that part works. I need to check one of the values that comes back to know if it was successful or not. That's where it's failing. And as far as I can tell, it's telling me that "success" is not equal to "success".

NSDictionary *jsonArray = [NSJSONSerialization JSONObjectWithData: response options: NSJSONReadingMutableContainers error: &err];

NSString *result = [jsonArray valueForKey:@"result"];
NSLog(@"%@",result);

if ([result isEqual:@"success"]) {

The log shows "result" is getting set as "success", but it never seems to evaluate as true.

If I set "result" manually:

NSString *result = @"success";

...it gets into the if statement just fine, so it seems like there's something I'm missing that's pointing to a data type or something similar... I'm just at a loss of what else to try at this point.

I'm normally a web dev, but I'm new to iOS, so my debugging is still a little lacking in xcode but I'm familiar with general logic and such. Any help you guys could give me would be fantastic!

Edit:

NSLog showing the JSON coming back from the webservice:

2014-01-10 16:22:42.568 LoginTest[1640:70b] (
    {
        code = 1;
        fname = Joe;
        lname = Tests;
        result = success;
        token = 2555f13bce42b14cdc9e60b923bb2b20;
        vendornum = 50000000;
    }
)

Edit - final working code:

NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: response options: NSJSONReadingMutableContainers error: &err];

NSLog(@"jsonArray: %@", jsonArray);

NSString *result = [jsonArray[0] objectForKey:@"result"];
NSLog(@"%@",result);

if ([result isEqual:@"success"]) {

Answer 1

Earlier you commented (from a now removed answer) that -isEqualToString: threw an unrecognized selector. I believe it was -[__NSCFArray -isEqualToString:] or something very similar.

Based on your comment, you don't have "success", you have [ "success" ] in your JSON.

That is an array which wraps the value of a string. You need to get the first element of the array and use that.

[result[0] isEqual:@"success"]

---

Based on the output in your log, your JSON is not an object

{
  …
  "result" = "success"
  …
}

It is an array with only one object in it.

[
  {
    …
    "result" = "success"
    …
  }
]

You are working with an array of data so the output of -valueForKey: will be an array of data.

@MartinR is correct, it may be clearer to use

[jsonArray[0] objectForKey:@"result"]

to get the result.

Answer 2

You didn't show us the actual output of the log. That's bad. Deducing from your comments, it should have shown something like

(
    "success"
)

which is the description of an array object (NSArray) containing a string, rather than the string object itself.

If this is indeed the case, then you need to get the (only? first?) element in the array and compare that using isEqual: or isEqualToString:.

Answer 3

if we want to compare two NSString we use [str1 isEqualToString:str2]; You should do same instead of isEqual:

isEqual: compares a string to an object, and will return NO if the object is not a string. do it if you are not sure if object is NSString.

`isEqualToString:` use it when you are sure both Objects are NSString.