I'm writing a form with 4 <select> elements. They all have the same options and I would like to disable, hide, or remove the selected option from one <select> in the other <select> elements with the same options in order to prevent the user to select the same option in multiple <select> elements.

No jQuery, only plain JavaScript please.

If possible I would like the first option to always display in all <select> elements:

<option class="select-items" selected>Sélectionnez..</option>

Here is the HTML for one <select>:

<select class="custom-select  mb-3" id="name_typage_0">
  <option class="select-items" selected>Sélectionnez..</option>
  <option class="select-items" value="designation">Désignation</option>
  <option class="select-items" value="email">Email</option>
  <option class="select-items" value="ville">Ville</option>
  <option class="select-items" value="secteur_activite">Secteur d'activité</option>
</select>

Here is part of my JavaScript:

const custSelec = document.querySelectorAll('.custom-select');
custSelec.forEach(function(item){
   item.addEventListener('change', function(){
      if(item.options[item.selectedIndex].text == 'Sélectionnez..'){
         count = -1;
      }else{
         count = 1;
      total += count;
     pteur.textContent = ` ${total}/${custSelec.length -1}`;

I'm writing a form with 4 <select> elements. They all have the same options and I would like to disable, hide, or remove the selected option from one <select> in the other <select> elements with the same options in order to prevent the user to select the same option in multiple <select> elements.

No jQuery, only plain JavaScript please.

If possible I would like the first option to always display in all <select> elements:

<option class="select-items" selected>Sélectionnez..</option>

Here is the HTML for one <select>:

<select class="custom-select  mb-3" id="name_typage_0">
  <option class="select-items" selected>Sélectionnez..</option>
  <option class="select-items" value="designation">Désignation</option>
  <option class="select-items" value="email">Email</option>
  <option class="select-items" value="ville">Ville</option>
  <option class="select-items" value="secteur_activite">Secteur d'activité</option>
</select>

Here is part of my JavaScript:

const custSelec = document.querySelectorAll('.custom-select');
custSelec.forEach(function(item){
   item.addEventListener('change', function(){
      if(item.options[item.selectedIndex].text == 'Sélectionnez..'){
         count = -1;
      }else{
         count = 1;
      total += count;
     pteur.textContent = ` ${total}/${custSelec.length -1}`;

• javascript
• html
• html-select

• You can keep the first option in another select and show/hide the current select on the click event listener of that option – A Rogue Otaku Commented May 13, 2019 at 15:53
• What would you prefer to do? 1.) Disable the other options? 2.) Hide the other options? 3.) Remove the other options? – scunliffe Commented May 13, 2019 at 16:59
• 1 With UI/UX in mind (apparently a must now), i would say that disable would be best. But ultimately any help is fine ^^ – Florent Vicente Commented May 14, 2019 at 7:21

3 Answers 3

In your change event listener, you can get the current set of selected values from all <select> elements in the group, and then loop through each element's options to both disable the options currently selected elsewhere in the group as well as re-enable any options that were previously selected but have since been changed. You can avoid disabling the first "label" option in each of your selects by checking the value before disabling / enabling options.

You could use this same approach to hide or remove options keeping in mind that there are some browser patibility issues when trying to hide <option> elements and that you would need some additional code to store the plete list of options if you were going to remove and restore them.

const selects = document.querySelectorAll('.select-group');
selects.forEach((elem) => {
  elem.addEventListener('change', (event) => {
    const values = Array.from(selects).map((select) => select.value);
    for (const select of selects) {
      select.querySelectorAll('option').forEach((option) => {
        const value = option.value;
        if (value &&  value !== select.value && values.includes(value)) {
          option.disabled = true;
        } else {
          option.disabled = false;
        }
      });
    }
  });
});

<select class="select-group">
  <option value="">Select...</option> 
  <option value="first">First Value</option> 
  <option value="second">Second Value</option>
  <option value="third">Third Value</option>
</select>
<select class="select-group">
  <option value="">Select...</option> 
  <option value="first">First Value</option> 
  <option value="second">Second Value</option>
  <option value="third">Third Value</option>
</select>
<select class="select-group">
  <option value="">Select...</option> 
  <option value="first">First Value</option> 
  <option value="second">Second Value</option>
  <option value="third">Third Value</option>
</select>

Thanks a lot for your help! I added a small 'if' to fix my bug and it works perfectly (until the next bug ^^):

if(value !== ""){
option.disabled = true;
}

Or I could just :

if (value && value !== select.value && values.includes(value) && value !== "") {
option.disabled = true;            
} 

Another difficulty when you begin : learn to write simple code ^^z