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select2/pages/12.programmatic-control/01.methods/docs.md
2017-09-08 14:23:33 -04:00

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---
title: Methods
taxonomy:
category: docs
process:
twig: true
never_cache_twig: true
---
Select2 supports methods that allow programmatic control of the component.
## Selecting a value
To programmatically select a value for a Select2 control, use the jQuery `.val()` method:
```
$('select').val('US'); // Select the option with a value of 'US'
$('select').trigger('change'); // Notify any JS components that the value changed
```
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.
### Limiting the scope of the `change` event
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:
```
$('select').val('US'); // Change the value or make some change to the internal state
$('select').trigger('change.select2'); // Notify only Select2 of changes
```
## Retrieving the selected values
There are two ways to programmatically access the selection data: using `.select2('data')`, or by using a jQuery selector.
### Using the `data` method
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>).
```
$('select').select2('data');
```
### Using a jQuery selector
Selected items can also be accessed via the `:selected` jQuery selector:
```
$('select').find(':selected');
```
It is possible to extend the `<option>` elements representing selection with the HTML data-* attributes containing arbitrary data from the source data objects:
```
$('select').select2({
// ...
templateSelection: function (data, container) {
$(data.element).attr('data-custom-attribute', data.customValue);
return data.text;
}
});
// Retrieve custom attribute value of the first selected element
$('select').find(':selected').attr('data-custom-attribute')
```
## Opening the dropdown
Methods handled directly by Select2 can be invoked by passing the name of the method to `.select2(...)`.
The `open` method will cause the dropdown menu to open, displaying the selectable options:
```
$('select').select2('open');
```
## Closing the dropdown
The `close` method will cause the dropdown menu to close, hiding the selectable options:
```
$('select').select2('close');
```
## Destroying the Select2 control
The `destroy` method will remove the Select2 widget from the target element. It will revert back to a standard `select` control:
```
$('select').select2('destroy');
```
## Clearing selections
You may clear all current selections in a Select2 control by setting the value of the control to `null`:
```
$('select').val(null).trigger('change');
```
## Examples
<div class="s2-example">
<label for="select2-single">Single select</label>
<button class="js-programmatic-set-val button" aria-label="Set Select2 option">
Set "California"
</button>
<button class="js-programmatic-open button">
Open
</button>
<button class="js-programmatic-close button">
Close
</button>
<button class="js-programmatic-destroy button">
Destroy
</button>
<button class="js-programmatic-init button">
Re-initialize
</button>
<p>
<select id="select2-single" class="js-example-programmatic js-states form-control"></select>
</p>
<label for="select2-multi">Multiple select</label>
<button type="button" class="js-programmatic-multi-set-val button" aria-label="Programmatically set Select2 options">
Set to California and Alabama
</button>
<button type="button" class="js-programmatic-multi-clear button" aria-label="Programmatically clear Select2 options">
Clear
</button>
<p>
<select id="select2-multi" class="js-example-programmatic-multi js-states form-control" multiple="multiple"></select>
</p>
</div>
<pre data-fill-from=".js-code-programmatic"></pre>
<script type="text/javascript" class="js-code-programmatic">
var $example = $(".js-example-programmatic").select2();
var $exampleMulti = $(".js-example-programmatic-multi").select2();
$(".js-programmatic-set-val").on("click", function () {
$example.val("CA").trigger("change");
});
$(".js-programmatic-open").on("click", function () {
$example.select2("open");
});
$(".js-programmatic-close").on("click", function () {
$example.select2("close");
});
$(".js-programmatic-init").on("click", function () {
$example.select2();
});
$(".js-programmatic-destroy").on("click", function () {
$example.select2("destroy");
});
$(".js-programmatic-multi-set-val").on("click", function () {
$exampleMulti.val(["CA", "AL"]).trigger("change");
});
$(".js-programmatic-multi-clear").on("click", function () {
$exampleMulti.val(null).trigger("change");
});
</script>