Tutorials References Menu

JS Reference

JS by Category JS by Alphabet

JavaScript

JS Array JS Boolean JS Classes JS Date JS Error JS Global JS JSON JS Math JS Number JS Operators JS RegExp JS Statements JS String

HTML DOM

DOM Attributes DOM Document DOM Element DOM Events DOM Event Objects DOM HTMLCollection DOM Location DOM Navigator DOM Screen DOM Style
alignContent alignItems alignSelf animation animationDelay animationDirection animationDuration animationFillMode animationIterationCount animationName animationTimingFunction animationPlayState background backgroundAttachment backgroundColor backgroundImage backgroundPosition backgroundRepeat backgroundClip backgroundOrigin backgroundSize backfaceVisibility border borderBottom borderBottomColor borderBottomLeftRadius borderBottomRightRadius borderBottomStyle borderBottomWidth borderCollapse borderColor borderImage borderImageOutset borderImageRepeat borderImageSlice borderImageSource borderImageWidth borderLeft borderLeftColor borderLeftStyle borderLeftWidth borderRadius borderRight borderRightColor borderRightStyle borderRightWidth borderSpacing borderStyle borderTop borderTopColor borderTopLeftRadius borderTopRightRadius borderTopStyle borderTopWidth borderWidth bottom boxShadow boxSizing captionSide caretColor clear clip color columnCount columnFill columnGap columnRule columnRuleColor columnRuleStyle columnRuleWidth columns columnSpan columnWidth counterIncrement counterReset cursor direction display emptyCells filter flex flexBasis flexDirection flexFlow flexGrow flexShrink flexWrap cssFloat font fontFamily fontSize fontStyle fontVariant fontWeight fontSizeAdjust height isolation justifyContent left letterSpacing lineHeight listStyle listStyleImage listStylePosition listStyleType margin marginBottom marginLeft marginRight marginTop maxHeight maxWidth minHeight minWidth objectFit objectPosition opacity order orphans outline outlineColor outlineOffset outlineStyle outlineWidth overflow overflowX overflowY padding paddingBottom paddingLeft paddingRight paddingTop pageBreakAfter pageBreakBefore pageBreakInside perspective perspectiveOrigin position quotes resize right scrollBehavior tableLayout tabSize textAlign textAlignLast textDecoration textDecorationColor textDecorationLine textDecorationStyle textIndent textOverflow textShadow textTransform top transform transformOrigin transformStyle transition transitionProperty transitionDuration transitionTimingFunction transitionDelay unicodeBidi userSelect verticalAlign visibility width wordBreak wordSpacing wordWrap widows zIndex
DOM Window

Web APIs

API Console API Geolocation API History API Storage

HTML Objects

<a> <abbr> <address> <area> <article> <aside> <audio> <b> <base> <bdo> <blockquote> <body> <br> <button> <canvas> <caption> <cite> <code> <col> <colgroup> <datalist> <dd> <del> <details> <dfn> <dialog> <div> <dl> <dt> <em> <embed> <fieldset> <figcaption> <figure> <footer> <form> <head> <header> <h1> - <h6> <hr> <html> <i> <iframe> <img> <ins> <input> button <input> checkbox <input> color <input> date <input> datetime <input> datetime-local <input> email <input> file <input> hidden <input> image <input> month <input> number <input> password <input> radio <input> range <input> reset <input> search <input> submit <input> text <input> time <input> url <input> week <kbd> <label> <legend> <li> <link> <map> <mark> <menu> <menuitem> <meta> <meter> <nav> <object> <ol> <optgroup> <option> <output> <p> <param> <pre> <progress> <q> <s> <samp> <script> <section> <select> <small> <source> <span> <strong> <style> <sub> <summary> <sup> <table> <tbody> <td> <tfoot> <th> <thead> <tr> <textarea> <time> <title> <track> <u> <ul> <var> <video>

Other References

CSSStyleDeclaration JS Conversion


HTML DOM length Property

❮ Attribute Object

Example

Get the number of attributes of a <button> element:

var x = document.getElementsByTagName("BUTTON")[0].attributes.length;
Try it Yourself »

More "Try it Yourself" examples below.


Definition and Usage

The length property returns the number of nodes in a NamedNodeMap object.

A Node object's attributes is an example of a NamedNodeMap object.

This property is read-only.

Tip: Use the item() method to return a node at the specified index in a NamedNodeMap object.


Browser Support

Property
length Yes Yes Yes Yes Yes

Note: In Internet Explorer 8 and earlier, the length property for attributes will return the number of all possible attributes for an element.


Syntax

namednodemap.length


Technical Details

Return Value: A Number, representing the number of attribute nodes in the nodemap
DOM Version Core Level 1

More Examples

Example

Loop through all attributes of a <button> element and output the name of each attribute:

var txt = "";
var x = document.getElementById("myBtn").attributes;

var i;
for (i = 0; i < x.length; i++) {
  txt += "Attribute name: " + x[i].name + "<br>";
}
Try it Yourself »

Example

Find out how many attributes an <img> element have:

var x = document.getElementById("myImg").attributes.length;
Try it Yourself »

Example

Loop through all attributes of an <img> element and output each attribute's name and value:

var txt = "";
var x = document.getElementById("myImg");

var i;
for (i = 0; i < x.attributes.length; i++) {
  txt = txt + x.attributes[i].name + " = " + x.attributes[i].value + "<br>";
}
Try it Yourself »

❮ Attribute Object