具有OR条件的Objective-C IF语句

Question

What's wrong in this IF statement?

if ([currentElement isEqualToString:@"aaa" || currentElement isEqualToString:@"bbb"])

XCode says:

No visible @interface for 'NSString' declares the selector 'isEqualToString:isEqualToString:'

I'm into an NSXML Parser procedure if it can help, but I think it's not that the problem.

Answer 1

You must compare result of two method calls:

if ([currentElement isEqualToString:@"aaa"] || [currentElement isEqualToString:@"bbb"])

The code you have actually compiles as

if ([currentElement isEqualToString:(@"aaa"||currentElement) isEqualToString:@"bbb"])

that is compiler tries to call non-existing isEqualToString:isEqualToString: method of NSString