Objective c checking whether text field is empty

Question

Here's the code:

- (IBAction) charlieInputText:(id)sender {
    //getting value from text field when entered
    charlieInputSelf = [sender stringValue];

    if (charlieInputSelf != @"") {
        //(send field if not empty
    }
}

This sends it even when the field is empty; therefore, this does not work as I want it to.

Joshua Weinberg · Accepted Answer · 2015-12-13T19:02:36.347

88

Simply checks for nil and if length of text length is greater than 0 - not empty

if (textField.text && textField.text.length > 0)
{
   /* not empty - do something */
}
else
{
   /* what ever */
}

edited Dec 13 '15 at 19:02

answered Jul 04 '10 at 04:01

Joshua Weinberg

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15

I feel like Stack has become a more useful reference than any major platforms official documentation – ChuckKelly Feb 08 '14 at 09:55
3

Actually if textField is nil then textField.text.lenght == 0. So you can reduce the if to: `if (textField.text.lenght > 0)` – Victor Maia Aldecôa Jan 19 '15 at 21:01
Both conditions are mutually depended. Keep only one condition.Since 0&0=0, 1&1=1 – Saranjith Jul 31 '17 at 06:58

Gaurav Pandey · Answer 2 · 2015-01-14T05:56:11.797

57

We already have inbuilt method that return boolean value that indicates whether the text-entry objects has any text or not.

// In Obj-C
if ([textField hasText]) {
        //*    Do Something you have text
    }else{
         /* what ever */
    }

// In Swift

if textField.hasText {
    //*    Do Something you have text
}else{
     /* what ever */
}

edited Jan 14 '15 at 05:56

answered Sep 08 '14 at 14:36

Gaurav Pandey

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I did not know about hasText ! – DogCoffee Nov 19 '15 at 23:13
let clientName = clientNameTF.hasText() ? clientNameTF.text! : "Client Name" – DogCoffee Nov 19 '15 at 23:21
2

This is the most elegant answer! Thank you – Sonic Master Dec 07 '15 at 06:27

score 8 · Answer 3 · answered Jul 04 '10 at 12:19

8

Joshua has the right answer in the narrow case, but generally, you can't compare string objects using the == or != operators. You must use -isEqual: or -isEqualToString: This is because charlieImputSelf and @"" are actually pointers to objects. Although the two sequences of characters may be the same, they need not point at the same location in memory.

answered Jul 04 '10 at 12:19

JeremyP

84,577
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So if you would want to check if the value of the text field was equal to `Boo`, you'd have to use `if ([textField.text isEqualToString:@"Boo"])` instead of `if (textField.text == @"Boo")` – Douwe Maan Jul 04 '10 at 12:52
1

Yes (it's annoying I can't just enter 'yes' in this text box) – JeremyP Jul 04 '10 at 15:50

score 2 · Answer 4 · answered May 12 '12 at 22:39

Those 'work' in a way. However, I found that the user can just fill in the box with spaces. I found using regular expressions helps (though what I use is for words without spaces) I can't really figure out how to make allow spaces.

NSError *error = NULL;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"[ ]" options:NSRegularExpressionCaseInsensitive error:&error];

if (!([[inputField stringValue]isEqualTo:regex])) {
        NSLog(@"Found a match");
// Do stuff in here //
}

score 1 · Answer 5 · answered Oct 21 '14 at 19:39

1

The Most efficent way to do this is by using this

// set it into an NSString
NSString *yourText = yourVariable.text;

if([theText length] == 0])
{
 // Your Code if it is equal to zero
}
else
{
// of the field is not empty

}

answered Oct 21 '14 at 19:39

ScottMobile

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8

score 1 · Answer 6 · answered Apr 10 '15 at 23:12

Check whether text field is empty in Swift

  @IBOutlet weak var textField: NSTextField!
  @IBOutlet weak var multiLineTextField: NSTextField!

  @IBAction func textChanged(sender: AnyObject) {
    //println("text changed! \(textField.stringValue)")

    if textField.stringValue.isEmpty == false {
      multiLineTextField.becomeFirstResponder()
      multiLineTextField.editable = true
    } else {
      multiLineTextField.editable = false
    }
  }

score 1 · Answer 7 · answered Nov 08 '19 at 12:01

The easiest way to do it.

Create new NSString without " " (spaces)

NSString *textWithoutSpaces = [self.textField.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];

Now you have string without spaces. You just have to check is this string empty or not.

if (textWithoutSpaces != 0) {
 /* not empty - do something */
} else {
  /* empty - do something */
}

score 0 · Answer 8 · edited Oct 12 '19 at 06:39

-(void)insert{

    if ([_nameofView  isEqual: @""]) {
        UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"Alert"
                                                                       message:@"Fill the Name Field First."
                                                                preferredStyle:UIAlertControllerStyleAlert];

        UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
                                                              handler:^(UIAlertAction * action) {}];

        [alert addAction:defaultAction];
        [self presentViewController:alert animated:YES completion:nil];



    }
    else if ([_detailofview  isEqual: @""]){

        UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"Alert"
                                                                       message:@"Fill the Details Field First."
                                                                preferredStyle:UIAlertControllerStyleAlert];

        UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
                                                              handler:^(UIAlertAction * action) {}];

        [alert addAction:defaultAction];
        [self presentViewController:alert animated:YES completion:nil];

    }
    else{
        UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"Alert"
                                                                       message:@"Data Inserted Successfully."
                                                                preferredStyle:UIAlertControllerStyleAlert];

        UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
                                                              handler:^(UIAlertAction * action) {}];

        [alert addAction:defaultAction];
        [self presentViewController:alert animated:YES completion:nil];

    }
}

I would recommend that you add some explanatory text to your answer, or you risk having it deleted as 'low quality' (even though it may be a correct answer)! — Adrian Mole, Oct 12 '19 at 06:37

Objective c checking whether text field is empty

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