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    <blockquote> <p>So what counts as a "very big file" anyway? At which point is it prudent to use delegation over the simple 'arrayWithContentsofCSVFile'?</p> </blockquote> <p>The way that <code>CHCSVParser</code> <em>reads and parses</em> your CSV file is identical regardless of whether you're using the <code>NSArray</code> category method or directly interfacing with the delegate itself (you can see this for yourself <a href="https://github.com/davedelong/CHCSVParser/blob/master/CHCSVParser/CHCSVParser.m#L736" rel="nofollow">here</a>). So "a very big file" is really a CSV file which would be too large to hold in memory as an <code>NSArray</code> in its entirety. The memory consumption will depend both on the number of columns and the number of rows, so it's hard to give a definite limit. </p> <p>What this means is that the problems you get from using the <code>-arrayWithContentsOfCSV</code> with large files shouldn't manifest themselves as returning nil, but as low memory warnings and the like. The fact you're getting <code>nil</code> returned suggests something else is going on.</p> <p>Firstly, you say you've tried logging the file, so you know it exists - have you tried parsing a much smaller subset of that file? The problem might be that your CSV is badly formed. Or alternatively - and this is something I've had problems with myself when working with CSV on iOS - is your CSV encoded correctly? Sometimes if you're outputting directly from Excel you can end up with strange and weird text encodings that occasionally seem to break things.</p> <p>You can always breakpoint and step-through the parsing methods in <code>CHCSVParser</code> for yourself and see what's going on. I hope this is of some use to you. As you've discovered, Dave DeLong actually posts here quite a bit - if you're lucky he'll probably come along and share more wisdom than I can.</p>
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    1. COGreat answer! For the dynamically sized files i'm working with, I suppose it would be prudent to just go with the delegate implementation regardless then just to be on the safe side of memory. I think you also nailed the issue with the csv file. I'm working with two files that were both taken directly from a SQL database, but one I opened in excel and one I did not. Just so happens the former was the file that did not work - some funky characters appeared at the beginning of the file that should not have been there after closing excel. Many thanks for the thoughtful and correct response!
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