HTMLSelectElement

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 the autofocus 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 the disabled HTML attribute, which indicates whether the control is disabled. If it is disabled, it does not accept clicks.

HTMLSelectElement.form 只读

Returns a HTMLFormElement representing the form that this element is associated with. If this element is a descendant of a form element, then this attribute is the ID of that form element. If the element is not a descendant of a form element, then the attribute can be the ID of any form element in the same document.

HTMLSelectElement.labels 只读

Returns a NodeList containing the list of label elements associated with this select element.

HTMLSelectElement.length

Is an unsigned long representing the number of <option> elements in this select element.

HTMLSelectElement.multiple

Is a Boolean that reflects the multiple HTML attribute, which indicates whether multiple items can be selected.

HTMLSelectElement.name

Is a DOMString that reflects the name HTML attribute, containing the name of this control used by servers and DOM search functions.

HTMLSelectElement.options 只读

只读属性。返回当前select元素包括的option元素对象的集合。

HTMLSelectElement.required

Is a Boolean that reflects the required HTML attribute, which indicates whether the user is required to select a value before submitting the form.

HTMLSelectElement.selectedIndex

此属性返回一个长整型数值，代表第一个被选中的option元素。-1代表没有元素被选中。

HTMLSelectElement.size

Is a long that reflects the size HTML attribute, which contains the number of visible items in the control. The default is 1, unless multiple is true, in which case it is 4.

HTMLSelectElement.type 只读

Returns a DOMString the form control's type. When multiple is true, it returns "select-multiple"; otherwise, it returns "select-one".

HTMLSelectElement.validationMessage 只读

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 只读

Returns a ValidityState representing the validity state that this control is in.

HTMLSelectElement.value

Is a DOMString with the value of this form control, that is, of the first selected option.

HTMLSelectElement.willValidate只读

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 this select 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 returns false).

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 the name 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
alert(select.selectedIndex); // 1
// return the value of the selected option
alert(select.options[select.selectedIndex].value) // Second

Specifications

Browser compatibility

See also

• The <select> HTML element, implementing this interface.