HTMLSelectElement: add() method

The HTMLSelectElement.add() method adds an element to the collection of option elements for this select element.

Syntax

add(item)
add(item, before)

Parameters

item: An HTMLOptionElement or HTMLOptGroupElement
before Optional: An element of the collection, or an index of type long, representing the item should be inserted before. If this parameter is null (or the index does not exist), the new element is appended to the end of the collection.

Return value

None (undefined).

Exceptions

HierarchyRequestError DOMException: Thrown if the item passed to the method is an ancestor of the HTMLSelectElement.

Examples

undefined

Creating Elements from Scratch

const sel = document.createElement("select");
const opt1 = document.createElement("option");
const opt2 = document.createElement("option");

opt1.value = "1";
opt1.text = "Option: Value 1";

opt2.value = "2";
opt2.text = "Option: Value 2";

sel.add(opt1, null);
sel.add(opt2, null);

/*
  Produces the following, conceptually:

  <select>
    <option value="1">Option: Value 1</option>
    <option value="2">Option: Value 2</option>
  </select>
*/

The before parameter is optional. So the following is accepted.

sel.add(opt1);
sel.add(opt2);

Append to an Existing Collection

const sel = document.getElementById("existingList");

const opt = document.createElement("option");
opt.value = "3";
opt.text = "Option: Value 3";

sel.add(opt, null);

/*
  Takes the existing following select object:

  <select id="existingList">
    <option value="1">Option: Value 1</option>
    <option value="2">Option: Value 2</option>
  </select>

  And changes it to:

  <select id="existingList">
    <option value="1">Option: Value 1</option>
    <option value="2">Option: Value 2</option>
    <option value="3">Option: Value 3</option>
  </select>
*/

The before parameter is optional. So the following is accepted.

sel.add(opt);

Inserting to an Existing Collection

const sel = document.getElementById("existingList");

const opt = document.createElement("option");
opt.value = "3";
opt.text = "Option: Value 3";

sel.add(opt, sel.options[1]);

/*
  Takes the existing following select object:

  <select id="existingList">
    <option value="1">Option: Value 1</option>
    <option value="2">Option: Value 2</option>
  </select>

  And changes it to:

  <select id="existingList">
    <option value="1">Option: Value 1</option>
    <option value="3">Option: Value 3</option>
    <option value="2">Option: Value 2</option>
  </select>
*/

Specifications

HTML