iOS7 only returns 'NSInvalidArgumentException', reason: '-[__NSCFString containsString:]: [duplicate]

Answer 1

The method to check [NSString containsString:] is only available on iOS8, to do that on iOS7 you need to:

NSString *string = @"foo";
if ([string rangeOfString:@"oo"].location == NSNotFound) {

} else {

}

Answer 2

The problem is that containsString: is an iOS8 API and thus crashing under iOS7. You could just replace

[wordModel.word containsString:tappedSentence]

with

[wordModel.word rangeOfString:tappedSentence].location != NSNotFound

Answer 3

Your code crashing because you used [wordModel.word containsString:tappedSentence] containsString is available in iOS 8 and later. If you want use both iOS 7 and iOS 8 + then please use below code -

Implement containsString yourself in a category using rangeOfString:

@implementation NSString (Contains)

- (BOOL)myContainsString:(NSString*)other {
  NSRange range = [self rangeOfString:other];
  return range.length != 0;
}

Hope this will help you.