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/DOM

NodeList.length

length returns the number of items in a NodeList.

Syntax

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

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

Notes

Despite the location of this page in the reference, length is not a property of Element, but rather of a NodeList. NodeList objects are returned from a number of DOM methods, such as document.getElementsByTagName.

length is a very common property in DOM programming. It's normal to test the length of a list (to see if it exists at all) and to use it as the iterator in a for loop, as in the example above.

Specification

length

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 1 12 ? ? ? ?
Mobile
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support Yes Yes ? ? ? ? Yes

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https://developer.mozilla.org/en-US/docs/Web/API/NodeList/length