Validation to prevent duplicated values on input text

Question

Im trying to prevent duplicated values on inputs with same name when I click a submit button, but it is not working and i am not sure why... I need some help to understand why is not working? Thanks lot in advance!

this is my code:

I tried with a solution I found here which it worked "on input change" behavior, but it doesnt with button click... My button:

<button type="button" id="approve" class="positive valid" tabindex="-1">Approve</button>

and my jquery

$('#received').on('click',function() {
    var $current = $(this);
    if ($('input[name^="RE_SignedByID"]').val() == $current.val() && $('input[name^="RE_SignedByID"]').attr('tabindex') !== $current.attr('tabindex') ) {
    alert('You can not have duplicated ID´s');
       return false;                        
    }else {
       return true;
    }
});

I want to show an alert and prevent the submit. Thanks a lot for any help!

What's the value of `#received`? What are the values in the `RE_SignedByID` elements? It would help to see your HTML. — Rory McCrossan, Feb 07 '19 at 10:40
@RoryMcCrossan The values in RE_SignedBy are "id numbers" like "987812-1324" the #received is a button — Fernando Lopez, Feb 07 '19 at 10:43
In that case what is the purpose of checking the value of the button? Are you only intending to stop duplicate values in the `RE_SignedBy` fields? — Rory McCrossan, Feb 07 '19 at 10:44
Ahh that is what im doing wrong! I shoud check the values before the "on click" action? Yes onlöy want to stop duplicated values — Fernando Lopez, Feb 07 '19 at 10:47
@Tom Yes #recived is a submit, Im trying to check that tree input text with same 'name=" " ' dont have duplicated values (in this case an ID number) — Fernando Lopez, Feb 07 '19 at 10:53

score 0 · Accepted Answer · answered Feb 07 '19 at 10:53

0

The issue is because you're comparing the value of the clicked button to the first input[name^="RE_SignedByID"] element.

To fix this you could instead create an array of all the input[name^="RE_SignedByID"] values using map(). You can then dedupe this list and compare the resulting array lengths. If they are different there was a duplicate. Try this:

$('#received').on('click', function(e) {
  var values = $('input[name^="RE_SignedByID"]').map(function() {
    return this.value.trim();
  }).get();  
  var unique =  [...new Set(values)];

  if (values.length != unique.length) {
    e.preventDefault();
    alert('You can not have duplicated ID\'s');
  }
});

Note that [...new Set(values)] will not work in IE. If you need to support legacy browsers there are plenty of alternatives to dedupe an array. See this answer for more information.

answered Feb 07 '19 at 10:53

Rory McCrossan

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I see! To get the values on an Array would be the soution I think, Im doing the checking of the values wrong, Im realizing that now... I'll make some changes – Fernando Lopez Feb 07 '19 at 11:00
can I have unique like this? var unique = $('input[name^="RE_SignedByID"]').val(); – Fernando Lopez Feb 07 '19 at 11:15
No, as calling `val()` on a collection of elements will only read the first. This is why I suggested using `map()` to read the values from *all* the elements in to a single array – Rory McCrossan Feb 07 '19 at 11:16
Allright :) Im trying to replace [...new Set(values)] cause it will be a problem if it does not work on IE. Thanks Rory! – Fernando Lopez Feb 07 '19 at 11:23

score 0 · Answer 2 · answered Feb 14 '19 at 09:27

I could fix it! Here is the code... you can add a button event like:

$('#submit').on('click', function () { 


 var values = $('[name=RE_SignedByID]').map(function() {
                return this.value.trim();
                }).get(); 

                var values2= $('[name=RE_OwnersID]').map(function() {
                return this.value.trim();
                }).get(); 
                values.sort();
                values2.sort();
                for (var i = 0; i < values.length-1; i++) { 
                if( values[i] == values[i+1] && values[i] !=""){

                showAlert(translator.getTranslation(' You can not have duplicated signers ID\'s'));
                return false;
              //  break;
                }
                } 
                for (var i = 0; i < values2.length-1; i++) { 
                if( values2[i] == values2[i+1] && values2[i] !=""){

                showAlert(translator.getTranslation(' You can not have duplicated owners ID\'s'));
                return false;
              //  break;
                }
                }
 });

Validation to prevent duplicated values on input text

2 Answers2