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----
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-title: Methods
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-taxonomy:
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- category: docs
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-process:
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- twig: true
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-never_cache_twig: true
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----
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-
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-Select2 supports methods that allow programmatic control of the component.
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-
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-## Programmatically adding options
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-
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-New options can be added to a Select2 control programmatically by creating a new [Javascript `Option` object](https://developer.mozilla.org/en-US/docs/Web/API/HTMLOptionElement/Option) and appending it to the control:
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-
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-```
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-var data = {
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- id: 1,
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- text: 'Barn owl'
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-};
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-
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-var newOption = new Option(data.name, data.id, false, false);
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-$('#mySelect2').append(newOption).trigger('change');
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-```
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-
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-The third parameter of `new Option(...)` determines whether the item is "default selected"; i.e. it sets the `selected` attribute for the new option. The fourth parameter sets the options actual selected state - if set to `true`, the new option will be selected by default.
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-
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-### Create if not exists
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-
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-You can use `.find` to select the option if it already exists, and create it otherwise:
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-
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-```
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-// Set the value, creating a new option if necessary
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-if ($('#mySelect2').find("option[value='" + data.id + "']").length) {
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- $('#mySelect2').val(data.id).trigger('change');
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-} else {
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- // Create a DOM Option and pre-select by default
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- var newOption = new Option(data.name, data.id, true, true);
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- // Append it to the select
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- $('#mySelect2').append(newOption).trigger('change');
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-}
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-```
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-
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-## Selecting an option
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-
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-To programmatically select an option/value for a Select2 control, use the jQuery `.val()` method:
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-
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-```
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-$('#mySelect2').val('US'); // Select the option with a value of 'US'
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-$('#mySelect2').trigger('change'); // Notify any JS components that the value changed
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-```
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-
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-Select2 will listen for the `change` event on the `<select>` element that it is attached to. When you make any external changes that need to be reflected in Select2 (such as changing the value), you should trigger this event.
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-
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-### Preselecting options in an remotely-sourced (AJAX) Select2
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-
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-For Select2 controls that receive their data from an [AJAX source](/data-sources/ajax), using `.val()` will not work. The options won't exist yet, because the AJAX request is not fired until the control is opened and/or the user begins searching. This is further complicated by server-side filtering and pagination - there is no guarantee when a particular item will actually be loaded into the Select2 control!
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-
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-The best way to deal with this, therefore, is to simply add the preselected item as a new option. For remotely sourced data, this will probably involve creating a new API endpoint in your server-side application that can retrieve individual items:
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-
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-```
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-// Set up the Select2 control
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-$('#mySelect2').select2({
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- ajax: {
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- url: '/api/students'
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- }
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-});
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-
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-// Fetch the preselected item, and add to the control
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-var studentSelect = $('#mySelect2');
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-$.ajax({
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- type: 'GET',
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- url: '/api/students/s/' + studentId
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-}).then(function (data) {
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- // create the option and append to Select2
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- var option = new Option(data.full_name, data.id, true, true);
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- studentSelect.append(option).trigger('change');
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-
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- // manually trigger the `select2:select` event
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- studentSelect.trigger({
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- type: 'select2:select',
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- params: {
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- data: data
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- }
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- });
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-});
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-```
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-
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-Notice that we manually trigger the `select2:select` event and pass along the entire `data` object. This allows other handlers to [access additional properties of the selected item](/programmatic-control/events#triggering-events).
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-
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-### Limiting the scope of the `change` event
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-
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-It's common for other components to be listening to the `change` event, or for custom event handlers to be attached that may have side effects. To limit the scope to **only** notify Select2 of the change, use the `.select2` event namespace:
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-
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-```
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-$('#mySelect2').val('US'); // Change the value or make some change to the internal state
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-$('#mySelect2').trigger('change.select2'); // Notify only Select2 of changes
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-```
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-
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-## Retrieving the selected values
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-
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-There are two ways to programmatically access the selection data: using `.select2('data')`, or by using a jQuery selector.
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-
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-### Using the `data` method
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-
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-Calling `select2('data')` will return a JavaScript array of objects representing the current selection. Each object will contain all of the properties/values that were in the source data objects passed through `processResults` and `templateResult` callbacks (as in <a href="#data">Loading data from an array</a> and <a href="#ajax">Connecting to a remote data source</a>).
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-
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-```
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-$('#mySelect2').select2('data');
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-```
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-
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-### Using a jQuery selector
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-
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-Selected items can also be accessed via the `:selected` jQuery selector:
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-
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-```
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-$('#mySelect2').find(':selected');
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-```
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-
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-It is possible to extend the `<option>` elements representing selection with the HTML data-* attributes containing arbitrary data from the source data objects:
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-
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-```
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-$('#mySelect2').select2({
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- // ...
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- templateSelection: function (data, container) {
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- $(data.element).attr('data-custom-attribute', data.customValue);
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- return data.text;
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- }
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-});
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-
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-// Retrieve custom attribute value of the first selected element
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-$('#mySelect2').find(':selected').attr('data-custom-attribute')
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-```
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-
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-## Opening the dropdown
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-
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-Methods handled directly by Select2 can be invoked by passing the name of the method to `.select2(...)`.
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-
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-The `open` method will cause the dropdown menu to open, displaying the selectable options:
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-
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-```
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-$('#mySelect2').select2('open');
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-```
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-
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-## Closing the dropdown
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-
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-The `close` method will cause the dropdown menu to close, hiding the selectable options:
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-
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-```
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-$('#mySelect2').select2('close');
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-```
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-
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-## Checking if the plugin is initialized
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-
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-To test whether Select2 has been initialized on a particular DOM element, you can check for the `select2-hidden-accessible` class:
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-
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-```
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-if ($('#mySelect2').hasClass("select2-hidden-accessible")) {
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- // Select2 has been initialized
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-}
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-```
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-
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-See [this Stack Overflow answer](https://stackoverflow.com/a/29854133/2970321)).
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-
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-## Destroying the Select2 control
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-
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-The `destroy` method will remove the Select2 widget from the target element. It will revert back to a standard `select` control:
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-
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-```
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-$('#mySelect2').select2('destroy');
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-```
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-
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-## Clearing selections
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-
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-You may clear all current selections in a Select2 control by setting the value of the control to `null`:
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-
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-```
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-$('#mySelect2').val(null).trigger('change');
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-```
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-
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-## Examples
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-
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-<div class="s2-example">
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-
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- <label for="select2-single">Single select</label>
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-
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- <button class="js-programmatic-set-val button" aria-label="Set Select2 option">
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- Set "California"
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- </button>
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-
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- <button class="js-programmatic-open button">
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- Open
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- </button>
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-
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- <button class="js-programmatic-close button">
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- Close
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- </button>
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-
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- <button class="js-programmatic-destroy button">
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- Destroy
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- </button>
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-
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- <button class="js-programmatic-init button">
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- Re-initialize
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- </button>
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- <p>
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- <select id="select2-single" class="js-example-programmatic js-states form-control"></select>
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- </p>
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-
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- <label for="select2-multi">Multiple select</label>
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-
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- <button type="button" class="js-programmatic-multi-set-val button" aria-label="Programmatically set Select2 options">
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- Set to California and Alabama
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- </button>
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-
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- <button type="button" class="js-programmatic-multi-clear button" aria-label="Programmatically clear Select2 options">
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- Clear
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- </button>
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-
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- <p>
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- <select id="select2-multi" class="js-example-programmatic-multi js-states form-control" multiple="multiple"></select>
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- </p>
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-
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-</div>
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-
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-<pre data-fill-from=".js-code-programmatic"></pre>
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-
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-<script type="text/javascript" class="js-code-programmatic">
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-
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-var $example = $(".js-example-programmatic").select2();
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-var $exampleMulti = $(".js-example-programmatic-multi").select2();
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-
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-$(".js-programmatic-set-val").on("click", function () {
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- $example.val("CA").trigger("change");
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-});
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-
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-$(".js-programmatic-open").on("click", function () {
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- $example.select2("open");
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-});
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-
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-$(".js-programmatic-close").on("click", function () {
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- $example.select2("close");
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-});
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-
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-$(".js-programmatic-init").on("click", function () {
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- $example.select2();
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-});
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-
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-$(".js-programmatic-destroy").on("click", function () {
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- $example.select2("destroy");
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-});
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-
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-$(".js-programmatic-multi-set-val").on("click", function () {
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- $exampleMulti.val(["CA", "AL"]).trigger("change");
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-});
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-
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-$(".js-programmatic-multi-clear").on("click", function () {
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- $exampleMulti.val(null).trigger("change");
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-});
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-
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-</script>
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alexweissman