Why is my comparing if statement not working?

Question

Why is the following code (in cocoa) not working?

NSString *extension = [fileName pathExtension];
NSString *wantedExtension = @\"mp3\";
if(extension == wante         


        

Answer 1

Paul's answer is technically correct, but as stated in the NSString documentation, "When you know both objects are strings, this method [isEqualToString:] is a faster way to check equality than isEqual:." Thus, for your example code, the correct test is

if([extension isEqualToString:wantedExtension]) {
    ...
}

If extension is nil, the result will be false, even if wantedExtension is non-nil, since messaging nil in Objective-C returns 0 for BOOL return-valued functions.