I volontari di MDN non hanno ancora tradotto questo articolo in Italiano. Registrati per tradurlo tu.
The HTMLSelectElement
interface represents a <select>
HTML Element. These elements also share all of the properties and methods of other HTML elements via the HTMLElement
interface.
Properties
This interface inherits the properties of HTMLElement
, and of Element
and Node
.
HTMLSelectElement.autofocus
- Is a
Boolean
that reflects theautofocus
HTML attribute, which indicates whether the control should have input focus when the page loads, unless the user overrides it, for example by typing in a different control. Only one form-associated element in a document can have this attribute specified. HTMLSelectElement.disabled
- Is a
Boolean
that reflects thedisabled
HTML attribute, which indicates whether the control is disabled. If it is disabled, it does not accept clicks. HTMLSelectElement.form
Read only- Returns a
HTMLFormElement
representing the form that this element is associated with. If the element is not associated with of a<form>
element, then it returnsnull
. HTMLSelectElement.labels
Read only- Returns a
NodeList
containing the list of label elements associated with this select element. HTMLSelectElement.length
- Is a
unsigned long
representing the number of<option>
elements in thisselect
element. HTMLSelectElement.multiple
- Is a
Boolean
that reflects themultiple
HTML attribute, which indicates whether multiple items can be selected. HTMLSelectElement.name
- Is a
DOMString
that reflects thename
HTML attribute, containing the name of this control used by servers and DOM search functions. HTMLSelectElement.options
Read only- Returns a
HTMLOptionsCollection
containing the set of<option>
elements contained by this element. HTMLSelectElement.required
- Is a
Boolean
that reflects therequired
HTML attribute, which indicates whether the user is required to select a value before submitting the form. HTMLSelectElement.selectedIndex
- Is a
long
that reflects the index of the first selected<option>
element. The value-1
indicates no element is selected. HTMLSelectElement.selectedOptions
Read only- Returns a live
HTMLCollection
containing the set of options that are selected. HTMLSelectElement.size
- Is a
long
that reflects thesize
HTML attribute, which contains the number of visible items in the control. The default is 1, unlessmultiple
is true, in which case it is 4. HTMLSelectElement.type
Read only- Returns a
DOMString
the form control's type. Whenmultiple
istrue
, it returns"select-multiple"
; otherwise, it returns"select-one"
. HTMLSelectElement.validationMessage
Read only- Returns a
DOMString
containing a localized message that describes the validation constraints that the control does not satisfy (if any). This attribute is the empty string if the control is not a candidate for constraint validation (willValidate
is false), or it satisfies its constraints. HTMLSelectElement.validity
Read only- Returns a
ValidityState
representing the validity state that this control is in. HTMLSelectElement.value
- Is a
DOMString
representing the value of the form control (the first selected option). HTMLSelectElement.willValidate
Read only- Is a
Boolean
that indicates whether the button is a candidate for constraint validation. It is false if any conditions bar it from constraint validation.
Methods
This interface inherits the methods of HTMLElement
, and of Element
and Node
.
HTMLSelectElement.add()
- Adds an element to the collection of
option
elements for thisselect
element. HTMLSelectElement.blur()
- Removes input focus from this element. This method is now implemented on
HTMLElement
. HTMLSelectElement.checkValidity()
- Checks whether the element has any constraints and whether it satisfies them. If the element fails its constraints, the browser fires a cancelable
invalid
event at the element (and returnsfalse
). HTMLSelectElement.focus()
- Gives input focus to this element. This method is now implemented on
HTMLElement
. HTMLSelectElement.item()
- Gets an item from the options collection for this
<select>
element. You can also access an item by specifying the index in array-style brackets or parentheses, without calling this method explicitly. HTMLSelectElement.namedItem()
- Gets the item in the options collection with the specified name. The name string can match either the
id
or thename
attribute of an option node. You can also access an item by specifying the name in array-style brackets or parentheses, without calling this method explicitly. HTMLSelectElement.remove()
- Removes the element at the specified index from the options collection for this select element.
HTMLSelectElement.setCustomValidity()
- Sets the custom validity message for the selection element to the specified message. Use the empty string to indicate that the element does not have a custom validity error.
Example
Get information about the selected option
/* assuming we have the following HTML <select id='s'> <option>First</option> <option selected>Second</option> <option>Third</option> </select> */ var select = document.getElementById('s'); // return the index of the selected option console.log(select.selectedIndex); // 1 // return the value of the selected option console.log(select.options[select.selectedIndex].value) // Second
A better way to track changes to the user's selection is to watch for the change
event to occur on the <select>
. This will tell you when the value changes, and you can then update anything you need to. See the example provided in the documentation for the change
event for details.
Specifications
Specification | Status | Comment |
---|---|---|
WHATWG HTML Living Standard The definition of 'HTMLSelectElement' in that specification. |
Living Standard | Since the latest snapshot, HTML5, it adds the autocomplete property and the reportValidity() method. |
HTML5 The definition of 'HTMLSelectElement' in that specification. |
Recommendation | Is a snapshot of WHATWG HTML Living Standard. It adds the autofocus , form , required , labels , selectedOptions , willValidate , validity and validationMessage properties.The tabindex property and the blur() and focus() methods have been moved to HTMLElement .The methods item() , namedItem() , checkValidity() and setCustomValidity() . |
Document Object Model (DOM) Level 2 HTML Specification The definition of 'HTMLSelectElement' in that specification. |
Recommendation | options now returns an HTMLOptionsCollection .length now returns an unsigned long . |
Document Object Model (DOM) Level 1 Specification The definition of 'HTMLSelectElement' in that specification. |
Recommendation | Initial definition. |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | 1.0 | (Yes) | 1.0 (1.7 or earlier) [2] | 1.0 | 1.0 | 1.0 |
item() and namedItem() |
(Yes) | (Yes)[3] | 4.0 (2.0) | 8[3] | (Yes) | (Yes) |
setCustomValidity() , checkValidity() , willValidate , validationMessage , validity |
(Yes) | (Yes) | 4.0 (2.0) | (Yes) | (Yes) | ? |
selectedOptions |
(Yes) | (Yes) | 26 (26) | No support | (Yes) | (Yes) |
labels |
(Yes) | No support | No support[1] | No support | (Yes) | (Yes) |
Feature | Android | Chrome | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|
Basic support | 1.0 | 1.0 | 1.0 (1) | 1.0 | 1.0 | 1.0 | 1.0 |
item() and namedItem() |
? | ? | 4.0 (2.0) | 1.0 | ? | ? | (Yes) |
setCustomValidity() , checkValidity() , willValidate , validationMessage , validity |
? | ? | 4.0 (2.0) | 1.0 | ? | ? | ? |
selectedOptions |
? | ? | 26.0 (26) | 1.2 | ? | ? | (Yes) |
labels |
? | ? | No support[1] | No support[1] | ? | ? | (Yes) |
[1] See bug 556743.
[2] Historically, Firefox has allowed keyboard and mouse events to bubble up from the <option>
element to the parent <select>
element. This doesn't happen in Chrome, however, although this behavior is inconsistent across many browsers. For better Web compatibility (and for technical reasons), when Firefox is in multi-process mode and the <select>
element is displayed as a drop-down list. The behavior is unchanged if the <select>
is presented inline and it has either the multiple
attribute defined or a size
attribute set to more than 1. Rather than watching <option>
elements for events, you should watch for {event("change")}} events on <select>
. See bug 1090602 for details.
[3] namedItem does not appear to take the name
attribute into account (only the id
attribute) on Internet Explorer and Edge. There is a bug report to Microsoft about this.
See also
- The
<select>
HTML element, which implements this interface.