Question

I am trying to retrieve the values from my NSDictionary however I am running into errors, I was wondering if someone might be able to help me with my solution.

I have 18 values, not all are shown here that I am checking, when the correct key is reached I would like to take the value in the NSDictionary and pass it into one of my NSString variables.

Below is an example of what I am trying to do however like I say I am having several issues

for (id key in searchData) {
    if ([[searchData objectForKey:key] isEqualToString:@"Code"]) {
        codeSeries = [searchData objectForKey:key];
    }
    else if ([[searchData objectForKey:key] isEqualToString:@"ID"]) {
        IDSeries = [searchData objectForKey:key];
    }

    // ...

However, when I try to log out any of the values, they all return Null. I have checked the dictionary before hand and the values are all most definitely in there, so I am thinking there is something wrong with my code above.

Any help would be greatly appreciated.

Update

This is how I create the NSDictionary

//start of mymethod...

NSDictionary *sendSeriesDictionary = [[NSDictionary alloc] init];
    
    // Keys for sendSeriesDictionary
    NSArray *keys = [NSArray arrayWithObjects:@"Code", @"ID", nil];
    
    // Objects for keys that are for sendSeriesDictionary
    NSArray *objects = [NSArray arrayWithObjects: [NSNull null], IdString, nil];
    
    // Add keys and objects to NSDictionary
    sendSeriesDictionary = [NSDictionary dictionaryWithObjects:objects forKeys:keys];


[engineRequests SeriesSearch:sendSeriesDictionary]; // this is where I send the NSDictionary over to where I want to read it.

//end of mymethod

Answer 1

You’ve got several problems. First, you mix up keys and values (like Tom said). Second, you have a possible memory leak where you create the dictionary, or at least a unnecessary instantiation.

Try this for creating the dictionary:

// Keys for sendSeriesDictionary
NSArray *keys = [NSArray arrayWithObjects:@"Code", @"ID", nil];

// Objects for keys that are for sendSeriesDictionary
NSArray *objects = [NSArray arrayWithObjects: [NSNull null], IdString, nil];

// Add keys and objects to NSDictionary
NSDictionary *sendSeriesDictionary = [NSDictionary dictionaryWithObjects:objects forKeys:keys];

Retrieving the values can be done like this:

codeSeries = [searchData objectForKey:@"Code"];
IDSeries = [searchData objectForKey:@"ID"];

In your first loop you looped through all the keys, got their values and then compared those to the key again. Which makes no sense.