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

Use following lines of code

NSString *str_test = @"Example ";
NSCharacterSet *whitespaceSet = [NSCharacterSet whitespaceCharacterSet];
if([str_test rangeOfCharacterFromSet:whitespaceSet].location!=NSNotFound)
{
    NSLog(@"Found");
}

if you want to restrict user use below code

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    if([string isEqualToString:@" "])
    {
        return NO
    }
    else
    {
        return YES
    }
}

Answer 2

In Swift,

if you want to restrict the user, you can use contains()

For Example,

if userTextField.text!.contains(" "){
//your code here.....
}

Answer 3

Heres Swift 3 version

let whitespaceSet = NSCharacterSet.whitespaces
let range = string.rangeOfCharacter(from: whitespaceSet)
if let _ = range {
    return false
}
else {
    return true
}