Javascript events option in select

HTMLSelectElement

This interface inherits the properties of HTMLElement , and of Element and Node . HTMLSelectElement.autofocus A boolean value reflecting 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 A boolean value reflecting the disabled HTML attribute, which indicates whether the control is disabled. If it is disabled, it does not accept clicks. HTMLSelectElement.form Read only An HTMLFormElement referencing the form that this element is associated with. If the element is not associated with of a element, then it returns null . HTMLSelectElement.labels Read only A NodeList of elements associated with the element. HTMLSelectElement.length An unsigned long The number of elements in this select element. HTMLSelectElement.multiple A boolean value reflecting the multiple HTML attribute, which indicates whether multiple items can be selected. HTMLSelectElement.name A string reflecting the name HTML attribute, containing the name of this control used by servers and DOM search functions. HTMLSelectElement.options Read only An HTMLOptionsCollection representing the set of ( HTMLOptionElement ) elements contained by this element. HTMLSelectElement.required A boolean value reflecting the required HTML attribute, which indicates whether the user is required to select a value before submitting the form. HTMLSelectElement.selectedIndex A long reflecting the index of the first selected element. The value -1 indicates no element is selected. HTMLSelectElement.selectedOptions Read only An HTMLCollection representing the set of elements that are selected. HTMLSelectElement.size A long reflecting 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 Read only A string representing the form control’s type. When multiple is true , it returns «select-multiple» ; otherwise, it returns «select-one» . HTMLSelectElement.validationMessage Read only A string representing 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 A ValidityState reflecting the validity state that this control is in. HTMLSelectElement.value A string reflecting the value of the form control. Returns the value property of the first selected option element if there is one, otherwise the empty string. HTMLSelectElement.willValidate Read only A boolean value that indicates whether the button is a candidate for constraint validation. It is false if any conditions bar it from constraint validation.

Instance 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() Deprecated 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() Deprecated Gives input focus to this element. This method is now implemented on HTMLElement . HTMLSelectElement.item() Gets an item from the options collection for this 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.reportValidity() This method reports the problems with the constraints on the element, if any, to the user. If there are problems, it fires a cancelable invalid event at the element, and returns false ; if there are no problems, it returns true . 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.

Events

Listen to these events using addEventListener() or by assigning an event listener to the oneventname property of this interface: change event Fires when the user selects an option. input event Fires when the value of an , , or element has been changed.

Example

Get information about the selected option

/* assuming we have the following HTML First Second Third  */ const 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 . 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

Browser compatibility

See also

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и | JavaScript

В Mozilla Firefox и в IE не срабатывает клик, если щёлкать по уже выбранному пункту, и весь подсчёт сбивается.

 Арбуз Дыня Тыква   

Тип тега

HTMLSelectElement.type : получить тип

Возвращает select-one или select-multiple , если есть атрибут multiple .

.type)"> Арбуз Дыня Тыква  .type)" multiple> Арбуз Дыня Тыква 

HTMLSelectElement.multiple : получить и изменить тип

Возвращает false или true , если есть атрибут multiple .

.multiple = (this.nextElementSibling.multiple == false ? true : false)">button .multiple)"> Арбуз Дыня Тыква 

Количество пунктов

HTMLSelectElement.length : получить и изменить количество пунктов

Нажать (сперва 3 пункта, затем 1, затем 5) Арбуз Дыня Тыква 

HTMLSelectElement.add() : добавить новый пункт

Получить значение

select.value : выводится значение атрибута value или при его отсутствии текст выбранного тега option [whatwg.org].

this.value)"> Арбуз Дыня Тыква 

this.value)"> Арбуз Дыня Тыква 

this.options[this.selectedIndex].value)"> Арбуз Дыня Тыква 

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Javascript events option in select

Last updated: Jan 12, 2023
Reading time · 3 min

# Get the Value/Text of Select or Dropdown on Change

To get the value and text of a select element on change:

1. Add a change event listener to the select element.
2. Use the value property to get the value of the element, e.g. select.value .
3. Use the text property to get the text of the element, e.g. select.options[select.selectedIndex].text .

Here is the HTML for the examples.

Copied! 
DOCTYPE html> html lang="en"> head> title>bobbyhadz.comtitle> meta charset="UTF-8" /> head> body> select id="select" style="font-size: 3rem"> option value="">--Choose an option--option> option value="horse">Horse 🐴option> option value="wolf">Wolf 🐺option> option value="fox">Fox 🦊option> select> script src="index.js"> script> body> html> 

And here is the related JavaScript code.

Copied! 
const select = document.getElementById('select'); select.addEventListener('change', function handleChange(event)  console.log(event.target.value); // 👉️ get selected VALUE // 👇️ get selected VALUE even outside event handler console.log(select.options[select.selectedIndex].value); // 👇️ get selected TEXT in or outside event handler console.log(select.options[select.selectedIndex].text); >); 

We added a change event listener to the select element.

We used the target property on the event object. The target property is a reference to the object (element) on which the event was dispatched.

In the example, the event.target property points to the select element, because that is the element on which the event was dispatched.

# Read or set the value of a select element

The value property allows us to read or set the value of the select element.

Copied! 
const select = document.getElementById('select'); // ✅ Read value console.log(select.value); // 👉️ "" // ✅ Set value select.value = 'fox'; console.log(select.value); // 👉️ "fox" 

When setting the value of a select element, make sure to set it to one of the values of the option elements.

The options property on the select element returns an array-like object that contains all of the options of the select element.

Copied! 
const select = document.getElementById('select'); console.log(select.options); // 👉️ [option, option, option, option] select.addEventListener('change', function handleChange(event)  console.log(select.options); // 👉️ [option, option, option, option] >); 

# Get the index of the currently selected option element

We can use the selectedIndex property to get the index of the currently selected option .

Copied! 
const select = document.getElementById('select'); console.log(select.selectedIndex); select.addEventListener('change', function handleChange(event)  console.log(select.selectedIndex); >); 

Initially it is set to 0 , but if you console.log the selectedIndex in the handleChange function and change the selected element, you will see the index change.

# Get the text and value of the selected option using the index

The selectedIndex property can be used to get the index of the currently selected option element. The index can be used to get the element’s value and text .

Copied! 
const select = document.getElementById('select'); select.addEventListener('change', function handleChange(event)  // 👇️ get selected VALUE even outside event handler console.log(select.options[select.selectedIndex].value); // 👇️ get selected TEXT in or outside event handler console.log(select.options[select.selectedIndex].text); >); 

This approach can be used both inside and outside of an event handler function.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

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