How to get file extension (compare) - ios

Question

i´m parsing the filedirectory from dropbox into a mutablearray, to show it in a table view.
how can i compare the file extension? (.doc, or .jpg,....)
if ([[NSString stringWithFormat:#"%#",[test objectAtIndex:indexPath.row]] isEqualToString:#"??????"] ) {
[cell.extensionView setImage:[UIImage imageNamed:#"word.png"]];
}
isEqualToWhat? is it possible to use wildcards?

Answer 1

Don't use stringWithFormat unless you actually have a format. Your code would be much cleaner if you did something like this:
NSString *filename = [text objectAtIndex:indexPath.row];
NSString *ext = [filename pathExtension];
if ([ext isEqualToString:#"doc"]) {
[cell.extensionView setImage:[UIImage imageNamed:#"word.png"]];
} else if ([ext isEqualToString:#".jpg"]) {
[cell.extensionView setImage:[UIImage imageNamed:#"jpeg.png"]];
}
There is a better way than setting up this big if-else block. I imagine you have lots of different extensions you wish to check. Setup a dictionary with the extensions and images. Something like:
NSDictionary *extensionThumbnails = #{
#"doc" : [UIImage imageNamed:#"word.png"],
#"xls" : [UIImage imageNamed:#"excel.png"],
#"jpg" : [UIImage imageNamed:#"jpeg.png"]
};
Add an entry for each extension and image you have. Then your original code (now using modern Objective-C syntax) becomes:
NSString *filename = text[indexPath.row];
NSString *ext = [filename pathExtension];
UIImage *thumbnail = extensionThumbnails[ext];
if (!thumbnail) {
thumbnail = [UIImage imageNamed:#"unknown.png"];
}
[cell.extensionView setImage:thumbnail];