How to set selected value of jquery select2?

Question

This belong to codes prior to select2 version 4

I have a simple code of select2 that get data from ajax

Answer 1

To build ontop of @tomloprod's answer. By the odd chance that you are using x-editable, and have a select2(v4) field and have multiple items you need to pre-select. You can use the following piece of code:

$("#select2field").on("shown", function(e, editable){
    $(["test1", "test2", "test3", "test4"]).each(function(k, v){
        // Create a DOM Option and pre-select by default~
        var newOption = new Option(v.text, v.id, true, true);
        // Append it to the select
        $(editable.input.$input).append(newOption).trigger('change');
     });
});

and here it is in action:

var data = [
{
    id: 0,
    text: 'enhancement'
},
{
    id: 1,
    text: 'bug'
},
{
    id: 2,
    text: 'duplicate'
},
{
    id: 3,
    text: 'invalid'
},
{
    id: 4,
    text: 'wontfix'
}
];

$("#select2field").editable({
        type: "select2",
        url: './',
        name: 'select2field',
        savenochange: true,
        send: 'always',
        mode: 'inline',
        source: data,
        value: "bug, wontfix",
        tpl: '<select style="width: 201px;">',
        select2: {
            width: '201px',
            tags: true,
            tokenSeparators: [',', ' '],
            multiple: true,
            data:data
        },
        success: function(response, newValue) {
            console.log("success")
        },
        error: function(response, newValue) {
            if (response.status === 500) {
                return 'Service unavailable. Please try later.';
            } else {
                return response.responseJSON;
            }
        }
    });

var preselect= [
    {
        id: 1,
        text: 'bug'
    },
    {
    id: 4,
    text: 'wontfix'
}
];

 $("#select2field").on("shown", function(e, editable){
    $(preselect).each(function(k, v){
        // Create a DOM Option and pre-select by default~
        var newOption = new Option(v.text, v.id, true, true);
        // Append it to the select
        $(editable.input.$input).append(newOption).trigger('change');
     });
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.1/js/select2.min.js"></script>
<link href="//cdnjs.cloudflare.com/ajax/libs/select2/4.0.1/css/select2.min.css" rel="stylesheet" />

<link href="//cdnjs.cloudflare.com/ajax/libs/x-editable/1.5.0/bootstrap3-editable/css/bootstrap-editable.css" rel="stylesheet"/>
<script src="//cdnjs.cloudflare.com/ajax/libs/x-editable/1.5.0/bootstrap3-editable/js/bootstrap-editable.min.js"></script>

<a id="select2field">bug, wontfix</a>

I guess that this would work even if you aren't using x-editable. I hope that htis could help someone.

Answer 2

You can use this code:

    $('#country').select2("val", "Your_value").trigger('change');

Put your desired value instead of Your_value

Hope It will work :)

Answer 3

In the current version on select2 - v4.0.1 you can set the value like this:

var $example = $('.js-example-programmatic').select2();
$(".js-programmatic-set-val").on("click", function () { $example.val("CA").trigger("change"); });

// Option 2 if you can't trigger the change event.
var $exampleDestroy = $('.js-example-programmatic-destroy').select2();
$(".js-programmatic-set-val").on("click", function () { $exampleDestroy.val("CA").select2('destroy').select2(); });

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.1/js/select2.min.js"></script>
<link href="//cdnjs.cloudflare.com/ajax/libs/select2/4.0.1/css/select2.min.css" rel="stylesheet" />

using "trigger(change)"
<select class="js-example-programmatic">
  <optgroup label="Alaskan/Hawaiian Time Zone">
    <option value="AK">Alaska</option>
    <option value="HI">Hawaii</option>
  </optgroup>
  <optgroup label="Pacific Time Zone">
    <option value="CA">California</option>
    <option value="NV">Nevada</option>
    <option value="OR">Oregon</option>
    <option value="WA">Washington</option>
  </optgroup>
  <optgroup label="Mountain Time Zone">
    <option value="AZ">Arizona</option>
    <option value="CO">Colorado</option>
    <option value="ID">Idaho</option>
    <option value="MT">Montana</option>
    <option value="NE">Nebraska</option>
    <option value="NM">New Mexico</option>
    <option value="ND">North Dakota</option>
    <option value="UT">Utah</option>
    <option value="WY">Wyoming</option>
  </optgroup>
  <optgroup label="Central Time Zone">
    <option value="AL">Alabama</option>
    <option value="AR">Arkansas</option>
    <option value="IL">Illinois</option>
    <option value="IA">Iowa</option>
    <option value="KS">Kansas</option>
    <option value="KY">Kentucky</option>
    <option value="LA">Louisiana</option>
    <option value="MN">Minnesota</option>
    <option value="MS">Mississippi</option>
    <option value="MO">Missouri</option>
    <option value="OK">Oklahoma</option>
    <option value="SD">South Dakota</option>
    <option value="TX">Texas</option>
    <option value="TN">Tennessee</option>
    <option value="WI">Wisconsin</option>
  </optgroup>
  <optgroup label="Eastern Time Zone">
    <option value="CT">Connecticut</option>
    <option value="DE">Delaware</option>
    <option value="FL">Florida</option>
    <option value="GA">Georgia</option>
    <option value="IN">Indiana</option>
    <option value="ME">Maine</option>
    <option value="MD">Maryland</option>
    <option value="MA">Massachusetts</option>
    <option value="MI">Michigan</option>
    <option value="NH">New Hampshire</option>
    <option value="NJ">New Jersey</option>
    <option value="NY">New York</option>
    <option value="NC">North Carolina</option>
    <option value="OH">Ohio</option>
    <option value="PA">Pennsylvania</option>
    <option value="RI">Rhode Island</option>
    <option value="SC">South Carolina</option>
    <option value="VT">Vermont</option>
    <option value="VA">Virginia</option>
    <option value="WV">West Virginia</option>
  </optgroup>
</select>

using destroy: 
<select class="js-example-programmatic">
  <optgroup label="Alaskan/Hawaiian Time Zone">
    <option value="AK">Alaska</option>
    <option value="HI">Hawaii</option>
  </optgroup>
  <optgroup label="Pacific Time Zone">
    <option value="CA">California</option>
    <option value="NV">Nevada</option>
    <option value="OR">Oregon</option>
    <option value="WA">Washington</option>
  </optgroup>
  <optgroup label="Mountain Time Zone">
    <option value="AZ">Arizona</option>
    <option value="CO">Colorado</option>
    <option value="ID">Idaho</option>
    <option value="MT">Montana</option>
    <option value="NE">Nebraska</option>
    <option value="NM">New Mexico</option>
    <option value="ND">North Dakota</option>
    <option value="UT">Utah</option>
    <option value="WY">Wyoming</option>
  </optgroup>
  <optgroup label="Central Time Zone">
    <option value="AL">Alabama</option>
    <option value="AR">Arkansas</option>
    <option value="IL">Illinois</option>
    <option value="IA">Iowa</option>
    <option value="KS">Kansas</option>
    <option value="KY">Kentucky</option>
    <option value="LA">Louisiana</option>
    <option value="MN">Minnesota</option>
    <option value="MS">Mississippi</option>
    <option value="MO">Missouri</option>
    <option value="OK">Oklahoma</option>
    <option value="SD">South Dakota</option>
    <option value="TX">Texas</option>
    <option value="TN">Tennessee</option>
    <option value="WI">Wisconsin</option>
  </optgroup>
  <optgroup label="Eastern Time Zone">
    <option value="CT">Connecticut</option>
    <option value="DE">Delaware</option>
    <option value="FL">Florida</option>
    <option value="GA">Georgia</option>
    <option value="IN">Indiana</option>
    <option value="ME">Maine</option>
    <option value="MD">Maryland</option>
    <option value="MA">Massachusetts</option>
    <option value="MI">Michigan</option>
    <option value="NH">New Hampshire</option>
    <option value="NJ">New Jersey</option>
    <option value="NY">New York</option>
    <option value="NC">North Carolina</option>
    <option value="OH">Ohio</option>
    <option value="PA">Pennsylvania</option>
    <option value="RI">Rhode Island</option>
    <option value="SC">South Carolina</option>
    <option value="VT">Vermont</option>
    <option value="VA">Virginia</option>
    <option value="WV">West Virginia</option>
  </optgroup>
</select>

<button class="js-programmatic-set-val">set value</button>

Answer 4

SELECT2 < V4

---

Step #1: HTML

<input name="mySelect2" type="hidden" id="mySelect2">

Step #2: Create an instance of Select2

$("#mySelect2").select2({
      placeholder: "My Select 2",
      multiple: false,
      minimumInputLength: 1,
      ajax: {
          url: "/elements/all",
          dataType: 'json',
          quietMillis: 250,
          data: function(term, page) {
              return {
                  q: term,
              };
          },
          results: function(data, page) {
              return {results: data};
          },
          cache: true
      },
      formatResult: function(element){
          return element.text + ' (' + element.id + ')';
      },
      formatSelection: function(element){
          return element.text + ' (' + element.id + ')';
      },
      escapeMarkup: function(m) {
          return m;
      }
});

Step #3: Set your desired value

$("#mySelect2").select2('data', { id:"elementID", text: "Hello!"});

---

If you use select2 without AJAX you can do as follow:

<select name="mySelect2" id="mySelect2">
  <option value="0">One</option>
  <option value="1">Two</option>
  <option value="2">Three</option>
</select>

/* "One" will be the selected option */
$('[name=mySelect2]').val("0");

You can also do so:

$("#mySelect2").select2("val", "0");

---

SELECT2 V4

---

For select2 v4 you can append directly an option/s as follow:

<select id="myMultipleSelect2" multiple="" name="myMultipleSelect2[]">
    <option value="TheID" selected="selected">The text</option>                                                                   
</select>

Or with JQuery:

var $newOption = $("<option selected='selected'></option>").val("TheID").text("The text")
 
$("#myMultipleSelect2").append($newOption).trigger('change');

other example

$("#myMultipleSelect2").val(5).trigger('change');

Answer 5

For Ajax, use $(".select2").val("").trigger("change"). That should solve the problem.

Answer 6

HTML

<select id="lang" >
   <option value="php">php</option>
   <option value="asp">asp</option>
   <option value="java">java</option>
</select>

JS

 $("#lang").select2().val('php').trigger('change.select2');

source: https://select2.github.io/options.html