<p>Select2 also supports multi-value select boxes. The <code>select</code> below is declared with the <code>multiple</code> attribute. Select2 automatically picks up on this:</p>
<p>The placeholder can be declared via a <code>data-placeholder</code> attribute attached to the <code>select</code>, or via the <code>placeholder</code> configuration element as seen in the example code.</p>
<p>When placeholder is used for a non-multi-value select box, it requires that you include an empty <code><option></option></code> tag as your first option.</p>
<p>Optionally, a clear button (visible once a selection is made) is available to reset the select box back to the placeholder value.</p>
<p>Select2 uses a function to load result data. Here is a trivial example that creates choices that consist of user's input repeated a number of times:</p>
<p>In order to take advantage of custom data loading Select2 should be attached to an <code>input type='hidden'</code> tag, otherwise data is parsed from <code>select</code>'s <code>option</code> tags.</p>
<p>Select2 provides some shortcuts that make it easy to access local data stored in an array instead of having to write a <code>query</code> function mentioned in the example above.</p>
<p>Example below inlines the data by specifying an array in the <code>data</code> element. Items in such an array must have <code>id</code> and <code>text</code> keys.</p>
<p>
<inputtype="hidden"id="e10"style="width:300px"/>
</p>
<p>If your data does not have a <code>text</code> key, an alternative key can be specified as a string:</p>
<pclass="alert alert-warning">If this example stops working, you have most likely reached the usage limit for the GitHub Search API of 5 requests per minute. Please wait a few minutes and try again.</p>
<p>Select2 uses jQuery's <code>$.ajax</code> function to execute the remote call by default. An alternative <code>transport</code> function can be specified in the ajax settings, or an entirely custom implementation can be built by providing a custom <code>query</code> function instead of using the <code>ajax</code> helper.</p>
</div>
</article>
<articleclass="row"id="infinite">
<divclass="span12">
<h3>Infinite Scroll with Remote Data</h3>
<p>Select2 supports lazy-appending of results when the result list is scrolled to the end.
In order to enable the remote service must support some sort of a paging mechanism and
the query function given to Select2 must take advantage of it. The following example demonstrates
how this can be set up. Search for some keyword and then scroll the result list to the end to
<pclass="alert alert-warning">If this example stops working, you have most likely reached the usage limit for the GitHub Search API of 5 requests per minute. Please wait a few minutes and try again.</p>
Select2 supports drag and drop sorting of selected choices. Select2 does not, itself, provide the necessary code to perform dragging and dropping, instead it provides hooks that other libraries can use to provide the behavior. In this example we are using JQuery UI's <code>sortable()</code> plugin.
</p>
<pclass="alert alert-info">The sorting is only available when Select2 is attached to a hidden <code>input</code> field.</p>
<p>The dropdown below matches on custom attributes of the <code>option</code> tag. For example, the `blue` option can be matched by entering either `blue` or `cyan`:</p>
<p>Unlike other dropdowns on this page, this one filters results by query string normally, but returns the matched results sorted from shortest to longest by string length. Try typing 'e' and seeing how the results are sorted. This function is useful for sorting results by relevance to a user's query.</p>
<p>Select2's width can be set to a percentage of its parent to support responsive design. The two Select2 boxes below are styled to 50% and 75% width respectively.</p>
<p><selectmultiple="multiple"id="e18_2"style="width:75%"placeholder="Select a state"class="populate placeholder"></select><br/></p>
<pclass="alert alert-warning">Select2 will do its best to resolve the percent width specified via a css class, but it is not always possible. The best way to ensure that Select2 is using a percent based width is to inline the style declaration into the tag.</p>
In case that you need to disable certain options so that they can't be selected by the select2 interface, you can now pass in <code>disabled: true</code> with your data. Please note: This also works for incoming values from ajax. When attached to a <code><select></code> element, Select2 will respect its <code><option></code> elements' <code>disabled</code> property.
In the event that you need to lock certain selections so that they can't be removed by the select2 interface, you can now pass in <code>locked: true</code> with your data. Please note: This also works for incoming values from ajax.
<p>Select2's default matcher will ignore diacritics, making it easier for users to filter results in international selects. Type "aero" into the select below:</p>
Controls the <code>width</code> style attribute of the Select2 container div. The following values are supported:
<dl>
<dt>off</dt><dd>No width attribute will be set. Keep in mind that the container div copies classes from the source element so setting the width attribute may not always be necessary.</dd>
<dt>element</dt><dd>Uses javascript to calculate the width of the source element.</dd>
<dt>copy</dt><dd>Copies the value of the width style attribute set on the source element.</dd>
<p>When attached to a <code>select</code> resolves the <code>option</code> that should be used as the placeholder.
Can either be a function which given the <code>select</code> element should return the <code>option</code>
element or a string <code>first</code> to indicate that the first option should be used.</p>
<p>This option is useful when Select2's default of using the first option only if it has no value and no text is not suitable.</p>
</td></tr>
<tr><td>separator</td><td>string</td><td>
<p>
Separator character or string used to delimit ids in <code>value</code> attribute of the multi-valued selects.
The default delimiter is the <code>,</code> character.
</p>
</td></tr>
<tr>
<td>allowClear</td>
<td>boolean</td>
<td>
<p>
Whether or not a clear button is displayed when the select box has a selection. The
button,
when clicked, resets the value of the select box back to the placeholder, thus this option is
only
available when the placeholder is specified.
</p>
<p>This option only works when the placeholder is specified.</p>
<pclass="alert alert-warning">When attached to a <code>select</code> an <code>option</code> with an empty value must be provided.
This is the option that will be selected when the button is pressed since a select box requires
at least one selection <code>option</code>.</p>
<p>
Also, note that this option only works with
non-multi-value based selects because multi-value selects always provide such a button for every
selected option.
</p>
</td>
</tr>
<tr>
<td>multiple</td>
<td>boolean</td>
<td>
<p>
Whether or not Select2 allows selection of multiple values.
</p>
<p>When Select2 is attached to a <code>select</code> element this value will be ignored and <code>select</code>'s
<code>multiple</code> attribute will be used instead.
</p>
</td>
</tr>
<tr>
<td>closeOnSelect</td>
<td>boolean</td>
<td>
<p>
If set to false the dropdown is not closed after a selection is made, allowing for rapid selection of multiple items. By default this option is set to <code>true</code>.
</p>
<pclass="alert alert-info">
Only applies when configured in multi-select mode.
</p>
</td>
</tr>
<tr>
<td>openOnEnter</td>
<td>boolean</td>
<td>
<p>
If set to true the dropdown is opened when the user presses the enter key and Select2 is closed. By default this option is enabled.
</p>
</td>
</tr>
<tr><td>id</td><td>function</td><td>
Function used to get the id from the choice object or a string representing the key under which the id is stored.
Used to determine whether or not the search term matches an option when a built-in query function is used.
The built in query function is used when Select2 is attached to a <code>select</code>, or the <code>local</code> or <code>tags</code> helpers are used.
<tr><td>object</td><td>object</td><td>The selected result object returned from the <code>query</code> function.</td></tr>
<tr><td>container</td><td>jQuery object</td><td>jQuery wrapper of the node to which the selection should be appended.</td></tr>
<tr><td>escapeMarkup</td><td>function</td><td>Function that can be used to escape html markup. This is the function defined in the <code>escapeMarkup</code>option, or the default.</td></tr>
<tr><td><returns></td><td>string (optional)</td><td>Html string, a DOM element, or a jQuery object that renders the selection.</td></tr>
</table>
<p>The default implementation expects the object to have a <code>text</code> property that is returned.</p>
<p>The implementation may choose to append elements directly to the provided <code>container</code> object, or return a single value and have it automatically appended.</p>
<br><br>
<p>
When attached to a <code>select</code> the original <code><option></code> (or <optgroup>) element is accessible inside the specified function through the property <code>item.element</code>:
<tr><td>object</td><td>object</td><td>One of the result objects returned from the <code>query</code> function.</td></tr>
<tr><td>container</td><td>jQuery object</td><td>jQuery wrapper of the node that should contain the representation of the result.</td></tr>
<tr><td>query</td><td>object</td><td>The query object used to request this set of results.</td></tr>
<tr><td>escapeMarkup</td><td>function</td><td>Function used to escape markup in results. If you do not expect to render custom markup you should pass your text through this function to escape any markup that may have been accidentally returned. This function is configurable in options of select2.</td></tr>
<tr><td><returns></td><td>string (optional)</td><td>Html string, a DOM element, or a jQuery object that represents the result.</td></tr>
</table>
<p>The default implementation expects the object to have a <code>text</code> property that is returned.</p>
<p>The implementation may choose to append elements directly to the provided <code>container</code> object, or return a single value and have it automatically appended.</p>
<br><br>
<p>
When attached to a <code>select</code> the original <code><option></code> (or <optgroup>) element is accessible inside the specified function through the property <code>item.element</code>:
<tr><td>element</td><td>jQuery array</td><td>element Select2 is attached to.</td></tr>
<tr><td>callback</td><td>function</td><td>callback function that should be called with the data which is either an object in case of a single select or an array of objects in case of multi-select.</td></tr>
</table>
<pclass="alert alert-info">This function will only be called when there is initial input to be processed.</p>
Here is an example implementation used for tags. Tags are the simplest form of data where the id is also
<tr><td>input</td><td>string</td><td>The text entered into the search field so far.</td></tr>
<tr><td>selection</td><td>array</td><td>Array of objects representing the current selection.
Useful if tokenizer needs to filter out duplicates.</td></tr>
<tr><td>selectCallback</td><td>function</td><td>Callback that can be used to add objects to the selection.</td></tr>
<tr><td>opts</td><td>object</td><td>Options with which Select2 was initialized. Useful if tokenizer needs to access some properties in the options.</td></tr>
<tr><td><returns></td><td>string (optional)</td><td>Returns the string to which the input of
the search field should be set to. Usually this is the remainder, of any, of the string after
the tokens have been stripped. If <code>undefined</code> or <code>null</code> is returned the
<tr><td>options.element</td><td>jquery object</td><td>The element Select2 is attached to.</td></tr>
<tr><td>options.term</td><td>string</td><td>Search string entered by user.</td></tr>
<tr><td>options.page</td><td>int</td><td>1-based page number tracked by Select2 for use with infinite scrolling of results.</td></tr>
<tr><td>options.context</td><td>object</td><td>An object that persists across the lifecycle of queries for the same search term (the query to retrieve the initial results, and subsequent queries to retrieve more result pages for the same search term). When this function is first called for a new search term this object will be null. The user may choose to set any object in the <code>results.context</code> field - this object will then be used as the context parameter for all calls to the <code>query</code> method that will load more search results for the initial search term. The object will be reset back to null when a new search term is queried. This feature is useful when a page number is not easily mapped against the server side paging mechanism. For example, some server side paging mechanism may return a "continuation token" that needs to be passed back to them in order to retrieve the next page of search results.</td></tr>
<tr><td>result.results</td><td>[object]</td><td>Array of result objects. The default renderers expect objects with <code>id</code> and <code>text</code> keys. The <code>id</code> property is required, even if custom renderers are used. The object may also contain a <code>children</code> key if hierarchical data is displayed. The object may also contain a <code>disabled</code> boolean property indicating whether this result can be selected.</td></tr>
<tr><td>results.context</td><td>object</td><td>A user-defined object that should be made available as the <code>context</code> parameter to the <code>query</code> function on subsequent queries to load more result pages for the same search term. See the description of <ahref="#doc-query-options-context"><code>options.context</code></a> parameter.</td></tr>
<pclass="alert alert-warning">In order for this function to work Select2 should be attached to a <code>input type='hidden'</code> tag instead of a <code>select</code>.</p>
Options for the built in ajax query function. This object acts as a shortcut for having to manually write a function that performs ajax requests. The built-in function supports more advanced features such as throttling and dropping out-of-order responses.
<tr><td>transport</td><td>function</td><td>Function that will be used to perform the ajax request. Must be parameter-compatible with <code>$.ajax</code>. Defaults to <code>$.ajax</code> if not specified.
Allows the use of various ajax wrapper libraries such as: <ahref="http://www.protofunc.com/scripts/jquery/ajaxManager/">AjaxManager</a>. </td></tr>
<tr><td>url</td><td>string/function</td><td>String containing the ajax url or a function that returns such a string.</td></tr>
<tr><td>dataType</td><td>string</td><td>Data type for the request. <code>xml</code>, <code>json</code>, <code>jsonp</code>, other formats supported by jquery.</td></tr>
<tr><td>quietMillis</td><td>int</td><td>Number of milliseconds to wait for the user to stop typing before issuing the ajax request.</td></tr>
<tr><td>cache</td><td>boolean</td><td>If set to <code>false</code>, it will force requested pages not to be cached by the browser. Default is <code>false</code>.</td></tr>
<tr><td>jsonpCallback</td><td>string/function</td><td>The callback function name for a JSONP request. This value will be used instead of the random name automatically generated by jQuery. It is preferable to let jQuery generate a unique name as it'll make it easier to manage the requests and provide callbacks and error handling. You may want to specify the callback when you want to enable better browser caching of GET requests.</td></tr>
<tr><td>data</td><td>function</td><td>
Function to generate query parameters for the ajax request.
<tr><td>page</td><td>int</td><td>1-based page number tracked by Select2 for use with infinite scrolling of results.</td></tr>
<tr><td>context</td><td>object</td><td>See <ahref="#doc-query-options-callback"><code>options.context</code></a> parameter to the <ahref="#doc-query"><code>query</code></a> function above.</td></tr>
<tr><td><returns></td><td>object</td><td>Results object. See "options.callback" in the "query" function for format.</td></tr>
</table>
</td></tr>
<tr><td>params</td><td>object/function</td><td>An object or a function that returns an object that contains extra parameters that will be passed to the transport. For example it can be used to set the content type: <code>{contentType: "application/json;charset=utf-8"}</code></td></tr>
</table>
<pclass="alert alert-warning">In order for this function to work Select2 should be attached to a <code>input type='hidden'</code> tag instead of a <code>select</code>.</p>
<pclass="alert alert-info">For documentation of the data format see the <ahref="#doc-query">query</a> function.</p>
</td></tr>
<tr><td>data</td><td>array/object</td><td>
Options for the built in query function that works with arrays.
<p>If this element contains an array, each element in the array must contain <code>id</code> and <code>text</code> keys.</p>
<p>Alternatively, this element can be specified as an object in which <code>results</code> key must contain the data as an array and a <code>text</code> key can either be the name of the key in data items that contains text or a function that retrieves the text given a data element from the array.</p>
</td></tr>
<tr><td>tags</td><td>array/function</td><td>
Puts Select2 into 'tagging'mode where the user can add new choices and pre-existing tags are provided via
this options attribute which is either an <code>array</code> or a <code>function</code> that returns an
array of <code>objects</code> or <code>strings</code>. If <code>strings</code> are used instead of <code>objects</code>
they will be converted into an object that has an <code>id</code> and <code>text</code> attribute equal
Inline css that will be added to select2's container. Either an object containing css property/value key pairs or a function that returns such an object.
Inline css that will be added to select2's dropdown container. Either an object containing css property/value key pairs or a function that returns such an object.
<tr><td>clazz</td><td>string</td><td>Css class being copied.</td></tr>
<tr><td><returns></td><td>string</td><td>Css class to be applied or <code>null/undefined/''</code> to not apply it.</td></tr>
</table>
The default implementation always returns <code>null</code> thereby filtering out all classes.
</td></tr>
<tr><td>escapeMarkup</td><td>function</td><td>
<code>String escapeMarkup(String markup)</code>
<p>Function used to post-process markup returned from formatter functions. By default this function escapes html entities to prevent javascript injection.</p>
</td></tr>
<tr><td>selectOnBlur</td><td>boolean</td><td>
<p>Set to <code>true</code> if you want Select2 to select the currently highlighted option when it is blurred.</p>
</td></tr>
<tr><td>loadMorePadding</td><td>integer</td><td>
Defines how many pixels need to be below the fold before the next page is loaded. The default value is <code>0</code> which means the result list needs to be scrolled all the way to the bottom for the next page of results to be loaded. This option can be used to trigger the load sooner, possibly resulting in a smoother user experience.
</td></tr>
<tr><td>nextSearchTerm</td><td>function</td><td>
<p>Function used to determine what the next search term should be.</p>
<pclass="alert alert-info">Function can be used when the dropdown is configured in single and multi-select mode. It is triggered after selecting an item. In single mode it is also triggered after initSelection (when provided).</p>
<p>Gets or sets the selection. If the <code>value</code> parameter is not specified, the <code>id</code> attribute of the currently selected element is returned. If the <code>value</code> parameter is specified it will become the current selection.</p>
<tr><td>triggerChange (optional)</td><td>boolean</td><td>Whether or not a <code>change</code> event should be triggered. <code>false</code> by default.</td></tr>
<p><code>val</code> method invoked on a single-select with an unset value will return <code>""</code>, while a <code>val</code> method invoked on an empty multi-select will return <code>[]</code>.</p>
Example: <preclass="prettyprint">alert("Selected value is: "+$("#e8").select2("val")); $("#e8").select2("val", "CA");</pre>
<pclass="alert alert-info">Notice that in order to use this method you must define the <code>initSelection</code> function in the options so Select2 knows how to transform the id of the object you pass in <code>val()</code> to the full object it needs to render selection. If you are attaching to a <code>select</code> element this function is already provided for you.</p>
<divclass="row">
<divclass="span12"><h3>data</h3></div>
</div>
<p>Gets or sets the selection. Analogous to <code>val</code> method, but works with objects instead of ids.</p>
<p><code>data</code> method invoked on a single-select with an unset value will return <code>null</code>, while a <code>data</code> method invoked on an empty multi-select will return <code>[]</code>.</p>
<p>Notifies Select2 that a drag and drop sorting operation has started. Select2 will hide all non-selection list items such as the search container, etc.
<p>Notifies Select2 that a drag and drop sorting operation has finished. Select2 will re-display any elements previously hidden and update the selection of the element it is attached to.
Select2 exposes its default options via the <code>$.fn.select2.defaults</code> object. Properties changed in this object (same properties configurable through the constructor) will take effect for every instance created after the change.
