Question

I have an application in which I have to perform validations on password and confirm password. This is my criteria for password field:

1. First letter should be capital.
2. Password should be more than above 6 values.
3. At least one special key should be present.
4. At least 1 numeric value should be entered in password.

If all this criteria are present then only password is accepted.

Answer 1

This should work:

- (BOOL)passwordIsValid:(NSString *)password {

    // 1. Upper case.
    if (![[NSCharacterSet uppercaseLetterCharacterSet] characterIsMember:[password characterAtIndex:0]])
        return NO;

    // 2. Length.
    if ([password length] < 6)
        return NO;

    // 3. Special characters.
    // Change the specialCharacters string to whatever matches your requirements.
    NSString *specialCharacters = @"!#€%&/()[]=?$§*'";
    if ([[password componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:specialCharacters]] count] < 2)
        return NO;

    // 4. Numbers.
    if ([[password componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"0123456789"]] count] < 2)
        return NO;

    return YES;
}

Testing it out:

NSLog(@"%@", [self passwordIsValid:@"Test#one"] ? @"YES" : @"NO"); // Prints NO.
NSLog(@"%@", [self passwordIsValid:@"Test#1"] ? @"YES" : @"NO"); // Prints YES.