How to know if a UITextField in iOS has blank spaces

Question

I have a UITextField where user can enter a name and save it. But, user should not be allowed to enter blank spaces in the textFiled.

1 - How can I find out,

Answer 1

if you really want to 'restrict' user from entering white space

you can implement the following method in UITextFieldDelegate

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range     replacementString:(NSString *)string { 

    NSString *resultingString = [textField.text stringByReplacingCharactersInRange: range withString: string];
    NSCharacterSet *whitespaceSet = [NSCharacterSet whitespaceCharacterSet];
    if  ([resultingString rangeOfCharacterFromSet:whitespaceSet].location == NSNotFound)      {
        return YES;
    }  else  {
        return NO;
    }
 }

If user enter space in the field, there is no change in the current text