How to check if NSDictionay key has a value efficiently when creating XML

I am creating some XML in objective C, I know how to do it however there is the possibility that there could be 800+ values I might be putting into XML, which I am getting from a NSArray of NSDictionaries.

So I was wondering if there is an efficient way of checking for nill or null in a keyvalue that's of type NSString.

Currently this is what my code looks like:

     NSMutableArray *xmlItems = [coreDataController readInstallForXML:selectedInstallID];

    for (int i = 0; i < [xmlItems count]; i++) {
        NSDictionary *currentXMLItem = [xmlItems objectAtIndex:i];

        [xmlWriter writeStartElement:@"Items"];
            [xmlWriter writeAttribute:@"insID" value:[currentXMLItem valueForKey:@"insID"]];
// there are about another 20 attributes I have to add here.
    }

// then write end elemtent etc.

In the code above I have no added any checking but I was hoping someone might have something better for me than adding a bunch of if statements for each attribute.

Solution

You can use [NSDictionary allKeysForObject:] to get all keys for the 'nil' values, so you have a list of keys to ignore.

Generating 800 items is not necessarily 'much' or 'slow'. You don't want to do that on the main thread anyway, so just make sure you perform it as a background operation.