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HTMLOptionsCollection: length property

The length property of the HTMLOptionsCollection interface returns the number of <option> elements in the collection. The property can get or set the size of the collection.

When setting length to a value smaller than the current, the options collection gets truncated; otherwise, new blank <option> elements are appended to the end of the <select>.

In this article

Value

An integer value representing the number of items in this HTMLOptionsCollection.

Example

js
const optCollection = document.getElementById("fruits").options; const origLength = optCollection.length; optCollection.length += 50; // adds 50 blank options to the collection optCollection.length = origLength; // truncates the list back to the original size

Specifications

Specification
HTML
# dom-htmloptionscollection-length-dev

Browser compatibility

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See also

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This page was last modified on Sep 28, 2024 by MDN contributors.

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  1. Document Object Model (DOM)
  2. HTMLOptionsCollection
  3. Instance properties
    1. length
    2. selectedIndex
  4. Instance methods
    1. add()
    2. remove()
  5. Inheritance
    1. HTMLCollection
  6. Related pages for DOM
    1. AbortController
    2. AbortSignal
    3. AbstractRange
    4. Attr
    5. CDATASection
    6. CharacterData
    7. Comment
    8. CustomEvent
    9. DOMError
    10. DOMException
    11. DOMImplementation
    12. DOMParser
    13. DOMTokenList
    14. Document
    15. DocumentFragment
    16. DocumentType
    17. Element
    18. Event
    19. EventTarget
    20. HTMLCollection
    21. MutationObserver
    22. MutationRecord
    23. NamedNodeMap
    24. Node
    25. NodeIterator
    26. NodeList
    27. ProcessingInstruction
    28. QuotaExceededError
    29. Range
    30. ShadowRoot
    31. StaticRange
    32. Text
    33. TreeWalker
    34. XMLDocument
    35. XPathEvaluator
    36. XPathExpression
    37. XPathResult
    38. XSLTProcessor
  7. Guides
    1. Anatomy of the DOM
    2. Attribute reflection
    3. Selection and traversal on the DOM tree
    4. Building and updating the DOM tree
    5. Working with events

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