regex - URL Validation (Objective-C)

Question

I am trying to validate a URL with this method:

Code:

- (BOOL) validateUrl: (NSString *) candidate {

    NSString *urlRegEx=
    @"((https?|ftp|gopher|telnet|file|notes|ms-help):((//)|(\\))+[wd:#@%/;$()~_?+-=\.&]*)";

    NSPredicate *urlTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", urlRegEx]; 
    return [urlTest evaluateWithObject:candidate];

}

It does not function. I think the problem is with the regular expression.

Answer 1

You can use + (id)URLWithString:(NSString *)URLString method of NSURL, which returns nil if the string is malformed.

Use if (URL && URL.scheme && URL.host) for checking URL.