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• 句法
• 范例
• 规范
• 浏览器兼容性
• 相关话题

NodeList.length property returns the number of items in a NodeList .

句法

numItems = nodeList.length
					

• numItems is an integer value representing the number of items in a NodeList .

范例

length property is often useful in DOM programming. It's often used to test the length of a list, to see if it exists at all. It's also commonly used as the iterator in a for loop, as in this example.

// All the paragraphs in the document
var items = document.getElementsByTagName("p");
// For each item in the list,
// append the entire element as a string of HTML
var gross = "";
for (var i = 0; i < items.length; i++) {
  gross += items[i].innerHTML;
}
// gross is now all the HTML for the paragraphs
					

规范

规范	状态	注释
DOM The definition of 'NodeList: length' in that specification.	实时标准

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
length	Chrome 1	Edge 12	Firefox Yes	IE ?	Opera Yes	Safari Yes	WebView Android Yes	Chrome Android Yes	Firefox Android Yes	Opera Android Yes	Safari iOS Yes	Samsung Internet Android Yes

图例

完整支持

完整支持

兼容性未知 ?

兼容性未知

元数据

• 最后修改： Jan 9, 2020

相关话题

1. DOM (文档对象模型)
2. NodeList
3. 特性

   1. length
4. 方法

   1. entries()
   2. forEach()
   3. item()
   4. keys()
   5. values()
5. DOM 相关页面

   1. AbortController
   2. AbortSignal
   3. AbstractRange
   4. Attr
   5. ByteString
   6. CDATASection
   7. CSSPrimitiveValue
   8. CSSValue
   9. CSSValueList
   10. CharacterData
   11. ChildNode
   12. 注释
   13. CustomEvent
   14. DOMConfiguration
   15. DOMError
   16. DOMErrorHandler
   17. DOMException
   18. DOMImplementation
   19. DOMImplementationList
   20. DOMImplementationRegistry
   21. DOMImplementationSource
   22. DOMLocator
   23. DOMObject
   24. DOMParser
   25. DOMPoint
   26. DOMPointInit
   27. DOMPointReadOnly
   28. DOMRect
   29. DOMString
   30. DOMTimeStamp
   31. DOMTokenList
   32. DOMUserData
   33. Document
   34. DocumentFragment
   35. DocumentType
   36. 元素
   37. ElementTraversal
   38. Entity
   39. EntityReference
   40. 事件
   41. EventTarget
   42. HTMLCollection
   43. MutationObserver
   44. 节点
   45. NodeFilter
   46. NodeIterator
   47. NonDocumentTypeChildNode
   48. ProcessingInstruction
   49. PromiseResolver
   50. 范围
   51. StaticRange
   52. 文本
   53. TextDecoder
   54. TextEncoder
   55. TimeRanges
   56. TreeWalker
   57. TypeInfo
   58. USVString
   59. UserDataHandler
   60. XMLDocument