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---
title: Add, select, or clear items
metadata:
description: Programmatically adding, selecting, and clearing options in a Select2 control.
taxonomy:
category: docs
---
## Creating new options in the dropdown
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:
```
var data = {
id: 1,
text: 'Barn owl'
};
var newOption = new Option(data.name, data.id, false, false);
$('#mySelect2').append(newOption).trigger('change');
```
The third parameter of `new Option(...)` determines whether the item is "default selected"; i.e. it sets the `selected` attribute for the new option. The fourth parameter sets the options actual selected state - if set to `true`, the new option will be selected by default.
### Create if not exists
You can use `.find` to select the option if it already exists, and create it otherwise:
```
// Set the value, creating a new option if necessary
if ($('#mySelect2').find("option[value='" + data.id + "']").length) {
$('#mySelect2').val(data.id).trigger('change');
} else {
// Create a DOM Option and pre-select by default
var newOption = new Option(data.name, data.id, true, true);
// Append it to the select
$('#mySelect2').append(newOption).trigger('change');
}
```
## Selecting an option
To programmatically select an option/item for a Select2 control, use the jQuery `.val()` method:
```
$('#mySelect2').val('US'); // Select the option with a value of 'US'
$('#mySelect2').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.
### Preselecting options in an remotely-sourced (AJAX) Select2
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!
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:
```
// Set up the Select2 control
$('#mySelect2').select2({
ajax: {
url: '/api/students'
}
});
// Fetch the preselected item, and add to the control
var studentSelect = $('#mySelect2');
$.ajax({
type: 'GET',
url: '/api/students/s/' + studentId
}).then(function (data) {
// create the option and append to Select2
var option = new Option(data.full_name, data.id, true, true);
studentSelect.append(option).trigger('change');
// manually trigger the `select2:select` event
studentSelect.trigger({
type: 'select2:select',
params: {
data: data
}
});
});
```
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).
### 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:
```
$('#mySelect2').val('US'); // Change the value or make some change to the internal state
$('#mySelect2').trigger('change.select2'); // Notify only Select2 of changes
```
## Clearing selections
You may clear all current selections in a Select2 control by setting the value of the control to `null`:
```
$('#mySelect2').val(null).trigger('change');
```

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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.
## Programmatically adding options
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:
```
var data = {
id: 1,
text: 'Barn owl'
};
var newOption = new Option(data.name, data.id, false, false);
$('#mySelect2').append(newOption).trigger('change');
```
The third parameter of `new Option(...)` determines whether the item is "default selected"; i.e. it sets the `selected` attribute for the new option. The fourth parameter sets the options actual selected state - if set to `true`, the new option will be selected by default.
### Create if not exists
You can use `.find` to select the option if it already exists, and create it otherwise:
```
// Set the value, creating a new option if necessary
if ($('#mySelect2').find("option[value='" + data.id + "']").length) {
$('#mySelect2').val(data.id).trigger('change');
} else {
// Create a DOM Option and pre-select by default
var newOption = new Option(data.name, data.id, true, true);
// Append it to the select
$('#mySelect2').append(newOption).trigger('change');
}
```
## Selecting an option
To programmatically select an option/value for a Select2 control, use the jQuery `.val()` method:
```
$('#mySelect2').val('US'); // Select the option with a value of 'US'
$('#mySelect2').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.
### Preselecting options in an remotely-sourced (AJAX) Select2
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!
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:
```
// Set up the Select2 control
$('#mySelect2').select2({
ajax: {
url: '/api/students'
}
});
// Fetch the preselected item, and add to the control
var studentSelect = $('#mySelect2');
$.ajax({
type: 'GET',
url: '/api/students/s/' + studentId
}).then(function (data) {
// create the option and append to Select2
var option = new Option(data.full_name, data.id, true, true);
studentSelect.append(option).trigger('change');
// manually trigger the `select2:select` event
studentSelect.trigger({
type: 'select2:select',
params: {
data: data
}
});
});
```
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).
### 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:
```
$('#mySelect2').val('US'); // Change the value or make some change to the internal state
$('#mySelect2').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>).
```
$('#mySelect2').select2('data');
```
### Using a jQuery selector
Selected items can also be accessed via the `:selected` jQuery selector:
```
$('#mySelect2').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:
```
$('#mySelect2').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
$('#mySelect2').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:
```
$('#mySelect2').select2('open');
```
## Closing the dropdown
The `close` method will cause the dropdown menu to close, hiding the selectable options:
```
$('#mySelect2').select2('close');
```
## Checking if the plugin is initialized
To test whether Select2 has been initialized on a particular DOM element, you can check for the `select2-hidden-accessible` class:
```
if ($('#mySelect2').hasClass("select2-hidden-accessible")) {
// Select2 has been initialized
}
```
See [this Stack Overflow answer](https://stackoverflow.com/a/29854133/2970321)).
## 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:
```
$('#mySelect2').select2('destroy');
```
## Clearing selections
You may clear all current selections in a Select2 control by setting the value of the control to `null`:
```
$('#mySelect2').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>

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pages/12.programmatic-control/02.retrieving-selections/docs.md Normal file
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---
title: Retrieving selections
metadata:
description: There are two ways to programmatically access the current selection data: using `.select2('data')`, or by using a jQuery selector.
taxonomy:
category: docs
---
There are two ways to programmatically access the current 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>).
```
$('#mySelect2').select2('data');
```
## Using a jQuery selector
Selected items can also be accessed via the `:selected` jQuery selector:
```
$('#mySelect2').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:
```
$('#mySelect2').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
$('#mySelect2').find(':selected').attr('data-custom-attribute')
```

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pages/12.programmatic-control/03.methods/docs.md Normal file
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@ -0,0 +1,132 @@
---
title: Methods
metadata:
description: Select2 has several built-in methods that allow programmatic control of the component.
taxonomy:
category: docs
process:
twig: true
never_cache_twig: true
---
Select2 has several built-in methods that allow programmatic control of the component.
## 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:
```
$('#mySelect2').select2('open');
```
## Closing the dropdown
The `close` method will cause the dropdown menu to close, hiding the selectable options:
```
$('#mySelect2').select2('close');
```
## Checking if the plugin is initialized
To test whether Select2 has been initialized on a particular DOM element, you can check for the `select2-hidden-accessible` class:
```
if ($('#mySelect2').hasClass("select2-hidden-accessible")) {
// Select2 has been initialized
}
```
See [this Stack Overflow answer](https://stackoverflow.com/a/29854133/2970321)).
## 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:
```
$('#mySelect2').select2('destroy');
```
## 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>

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@ -1,5 +1,7 @@
--- ---
title: Events title: Events
metadata:
description: Listening to Select2's built-in events, and manually triggering events on the Select2 component.
taxonomy: taxonomy:
category: docs category: docs
process: process:

6
pages/12.programmatic-control/chapter.md
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--- ---
title: Methods and Events title: Programmatic control
metadata:
description: Programmatically adding and selecting items, getting the current selections, manipulating the control, and working with Select2 events.
taxonomy: taxonomy:
category: docs category: docs
--- ---
# Methods and Events # Programmatic control