How do I get the information from a meta tag with JavaScript?

Question

The information I need is in a meta tag. How can I access the "content" data of the meta tag when property="video"?

HTML:

<meta property="video" content="http://video.com/video33353.mp4" />

Answer 1

You can use this:

function getMeta(metaName) {
  const metas = document.getElementsByTagName('meta');

  for (let i = 0; i < metas.length; i++) {
    if (metas[i].getAttribute('name') === metaName) {
      return metas[i].getAttribute('content');
    }
  }

  return '';
}

console.log(getMeta('video'));

Answer 2

The other answers should probably do the trick, but this one is simpler and does not require jQuery:

document.head.querySelector("[property~=video][content]").content;

The original question used an RDFa tag with a property="" attribute. For the normal HTML <meta name="" …> tags you could use something like:

document.querySelector('meta[name="description"]').content

Answer 3

One liner here

document.querySelector("meta[property='og:image']").getAttribute("content");

Answer 4

There is an easier way:

document.getElementsByName('name of metatag')[0].getAttribute('content')

Answer 5

function getMetaContentByName(name,content){
   var content = (content==null)?'content':content;
   return document.querySelector("meta[name='"+name+"']").getAttribute(content);
}

Used in this way:

getMetaContentByName("video");

The example on this page:

getMetaContentByName("twitter:domain");

Answer 6

If you use JQuery, you can use:

$("meta[property='video']").attr('content');

Answer 7

In Jquery you can achieve this with:

$("meta[property='video']");

In JavaScript you can achieve this with:

document.getElementsByTagName('meta').item(property='video');

Answer 8

Way - [ 1 ]

function getMetaContent(property, name){
    return document.head.querySelector("["+property+"="+name+"]").content;
}
console.log(getMetaContent('name', 'csrf-token'));

You may get error: Uncaught TypeError: Cannot read property 'getAttribute' of null

---

Way - [ 2 ]

function getMetaContent(name){
    return document.getElementsByTagName('meta')[name].getAttribute("content");
}
console.log(getMetaContent('csrf-token'));

You may get error: Uncaught TypeError: Cannot read property 'getAttribute' of null

---

Way - [ 3 ]

function getMetaContent(name){
    name = document.getElementsByTagName('meta')[name];
    if(name != undefined){
        name = name.getAttribute("content");
        if(name != undefined){
            return name;
        }
    }
    return null;
}
console.log(getMetaContent('csrf-token'));

Instead getting error, you get null, that is good.

Answer 9

Simple one, right?

document.head.querySelector("meta[property=video]").content

Answer 10

This code works for me

<meta name="text" property="text" content="This is text" />
<meta name="video" property="text" content="http://video.com/video33353.mp4" />

JS

var x = document.getElementsByTagName("META");
    var txt = "";
    var i;
    for (i = 0; i < x.length; i++) {
        if (x[i].name=="video")
        {
             alert(x[i].content);
         }

    }    

Example fiddle: http://jsfiddle.net/muthupandiant/ogfLwdwt/

Answer 11

function getDescription() {
    var info = document.getElementsByTagName('meta');
    return [].filter.call(info, function (val) {
        if(val.name === 'description') return val;
    })[0].content;
}

update version:

function getDesc() {
    var desc = document.head.querySelector('meta[name=description]');
    return desc ? desc.content : undefined;
}

Answer 12

My variant of the function:

const getMetaValue = (name) => {
  const element = document.querySelector(`meta[name="${name}"]`)
  return element?.getAttribute('content')
}

Answer 13

document.querySelector('meta[name=NAME_OF_THE_FIELD]').content

this way you can get the content of the meta.

Answer 14

Here's a function that will return the content of any meta tag and will memoize the result, avoiding unnecessary querying of the DOM.

var getMetaContent = (function(){
        var metas = {};
        var metaGetter = function(metaName){
            var theMetaContent, wasDOMQueried = true;;
            if (metas[metaName]) {
                theMetaContent = metas[metaName];
                wasDOMQueried = false;
            }
            else {
                 Array.prototype.forEach.call(document.getElementsByTagName("meta"), function(el) {
                    if (el.name === metaName) theMetaContent = el.content;
                    metas[metaName] = theMetaContent;
                });
            }
            console.log("Q:wasDOMQueried? A:" + wasDOMQueried);
            return theMetaContent;
        }
        return metaGetter;
    })();

getMetaContent("description"); /* getMetaContent console.logs the content of the description metatag. If invoked a second time it confirms that the DOM  was only queried once */

And here's an extended version that also queries for open graph tags, and uses Array#some:

var getMetaContent = (function(){
        var metas = {};
        var metaGetter = function(metaName){
            wasDOMQueried = true;
            if (metas[metaName]) {
                wasDOMQueried = false;
            }
            else {
                 Array.prototype.some.call(document.getElementsByTagName("meta"), function(el) {
                        if(el.name === metaName){
                           metas[metaName] = el.content;
                           return true;
                        }
                        if(el.getAttribute("property") === metaName){
                           metas[metaName] = el.content;
                           return true;
                        }
                        else{
                          metas[metaName] = "meta tag not found";
                        }  
                    });
            }
            console.info("Q:wasDOMQueried? A:" + wasDOMQueried);
            console.info(metas);
            return metas[metaName];
        }
        return metaGetter;
    })();

getMetaContent("video"); // "http://video.com/video33353.mp4"

Answer 15

I personally prefer to just get them in one object hash, then I can access them anywhere. This could easily be set to an injectable variable and then everything could have it and it only grabbed once.

By wrapping the function this can also be done as a one liner.

var meta = (function () {
    var m = document.querySelectorAll("meta"), r = {};
    for (var i = 0; i < m.length; i += 1) {
        r[m[i].getAttribute("name")] = m[i].getAttribute("content")
    }
    return r;
})();

Answer 16

FYI according to https://developer.mozilla.org/en-US/docs/Web/HTML/Element/meta global attributes are valid which means the id attribute can be used with getElementById.

Answer 17

<html>
<head>
<meta property="video" content="http://video.com/video33353.mp4" />
<meta name="video" content="http://video.com/video33353.mp4" />
</head>
<body>

<script>
var meta = document.getElementsByTagName("meta");
    size = meta.length;

for(var i=0; i<size; i++) {
    if (meta[i].getAttribute("property") === "video") {
        alert(meta[i].getAttribute("content"));
    }
}
meta = document.getElementsByTagName("meta")["video"].getAttribute("content");
alert(meta);
</script>
</body>
</html>

Demo

Answer 18

If you are interessted in a more far-reaching solution to get all meta tags you could use this piece of code

function getAllMetas() {
    var metas = document.getElementsByTagName('meta');
    var summary = [];
    Array.from(metas)
        .forEach((meta) => {
            var tempsum = {};
            var attributes = meta.getAttributeNames();
            attributes.forEach(function(attribute) {
                tempsum[attribute] = meta.getAttribute(attribute);
            });
            summary.push(tempsum);
        });
    return summary;
}

// usage
console.log(getAllMetas());

Answer 19

copy all meta values to a cache-object:

/* <meta name="video" content="some-video"> */

const meta = Array.from(document.querySelectorAll('meta[name]')).reduce((acc, meta) => (
  Object.assign(acc, { [meta.name]: meta.content })), {});

console.log(meta.video);

Answer 20

document.head.querySelector('meta[property=video]').content;

Answer 21

if the meta tag is:

<meta name="url" content="www.google.com" />

JQuery will be:

const url = $('meta[name="url"]').attr('content'); // url = 'www.google.com'

JavaScript will be: (It will return whole HTML)

const metaHtml = document.getElementsByTagName('meta').url // metaHtml = '<meta name="url" content="www.google.com" />'