CODEWITHSUNDEEP
javascriptdomprototypejs
Omer Bokhari
Omer Bokhari

Reputation: 59658

Creating a new DOM element from an HTML string using built-in DOM methods or Prototype

I have an HTML string representing an element: '<li>text</li>'. I'd like to append it to an element in the DOM (a ul in my case). How can I do this with Prototype or with DOM methods?

(I know i could do this easily in jQuery, but unfortunately we're not using jQuery.)

Upvotes: 979

Views: 1019330

Answers (30)

Mark Amery
Mark Amery

Reputation: 155155

HTML 5 introduced the <template> element which can be used for this purpose (as now described in the WhatWG spec and MDN docs).

A <template> element is used to declare fragments of HTML that can be utilized in scripts. The element is represented in the DOM as a HTMLTemplateElement which has a .content property of DocumentFragment type, to provide access to the template's contents. This means that you can convert an HTML string to DOM elements by setting the innerHTML of a <template> element, then reaching into the template's .content property.

Examples:

/**
 * @param {String} HTML representing a single node (which might be an Element,
                   a text node, or a comment).
 * @return {Node}
 */
function htmlToNode(html) {
    const template = document.createElement('template');
    template.innerHTML = html;
    const nNodes = template.content.childNodes.length;
    if (nNodes !== 1) {
        throw new Error(
            `html parameter must represent a single node; got ${nNodes}. ` +
            'Note that leading or trailing spaces around an element in your ' +
            'HTML, like " <img/> ", get parsed as text nodes neighbouring ' +
            'the element; call .trim() on your input to avoid this.'
        );
    }
    return template.content.firstChild;
}

const td = htmlToNode('<td>foo</td>'),
      div = htmlToNode('<div><span>nested</span> <span>stuff</span></div>');

/**
 * @param {String} HTML representing any number of sibling nodes
 * @return {NodeList} 
 */
function htmlToNodes(html) {
    const template = document.createElement('template');
    template.innerHTML = html;
    return template.content.childNodes;
}

const rows = htmlToNodes('<tr><td>foo</td></tr><tr><td>bar</td></tr>');

Note that similar approaches that use a different container element such as a div don't quite work. HTML has restrictions on what element types are allowed to exist inside which other element types; for instance, you can't put a td as a direct child of a div. This causes these elements to vanish if you try to set the innerHTML of a div to contain them. Since <template>s have no such restrictions on their content, this shortcoming doesn't apply when using a template.

Using <template>s was previously not always possible due to Internet Explorer not supporting <template>s, but IE support is almost never a consideration nowadays and Can I Use characterises <template>s as "baseline" functionality "widely available across major browsers". Except in the rare few cases where you find yourself writing web content for dead browsers, this approach will now reliably work for you.

Upvotes: 721

Tiera.3
Tiera.3

Reputation: 21

What about using outerHTML ?

*element*.appendChild( document.createElement('li')).outerHTML= '<li>text</li>' ;

The parameter for createElement doesn't need to match the element type specified in your string, but it does need to be a legal child of element

*element*.appendChild( document.createElement('a')).outerHTML= '<li>text</li>' ;

works just as well

Upvotes: 2

Radim Šafr&#225;n
Radim Šafr&#225;n

Reputation: 608

Solution - works with all browsers since IE 4.0

var htmlString = `<body><header class="text-1">Hello World</header><div id="table"><!--TABLE HERE--></div></body>`;
var tableString = `<table class="table"><thead><tr><th>th cell</th></tr></thead><tbody><tr><td>td cell</td></tr></tbody></table>`;


var doc = document.implementation.createHTMLDocument();
    doc.open();
    doc.write(htmlString);
    doc.getElementById('table').insertAdjacentHTML('beforeend', tableString);
    doc.close();

console.log(doc);

Or you can use DOMParser

var doc = (new DOMParser).parseFromString(htmlString, "text/html");
    doc.getElementById('table').insertAdjacentHTML('beforeend', tableString);

console.log(doc);

Upvotes: 5

osman akbacı
osman akbacı

Reputation: 47

Visit https://www.codegrepper.com/code-examples/javascript/convert+a+string+to+html+element+in+js

const stringToHtml = function (str) {
    var parser = new DOMParser();
    var doc = parser.parseFromString(str, 'text/html');
    return doc.body;
}

Upvotes: 1

realmag777
realmag777

Reputation: 2088

Example with latest JS:

<template id="woof-sd-feature-box">
<div class="woof-sd-feature-box" data-key="__KEY__" data-title="__TITLE__" data-data="__OPTIONS__">
    <h4>__TITLE__</h4>
    <div class="woof-sd-form-item-anchor">
        <img src="img/move.png" alt="">
    </div>
</div>

</template>

<script>
create(example_object) {
        let html = document.getElementById('woof-sd-feature-box').innerHTML;
        html = html.replaceAll('__KEY__', example_object.dataset.key);
        html = html.replaceAll('__TITLE__', example_object.dataset.title);
        html = html.replaceAll('__OPTIONS__', example_object.dataset.data);
        //convertion HTML to DOM element and prepending it into another element
        const dom = (new DOMParser()).parseFromString(html, "text/html");
        this.container.prepend(dom.querySelector('.woof-sd-feature-box'));
    }
</script>

Upvotes: -1

Crescent Fresh
Crescent Fresh

Reputation: 117028

Note: most current browsers support HTML <template> elements, which provide a more reliable way of turning creating elements from strings. See Mark Amery's answer below for details.

For older browsers, and node/jsdom: (which doesn't yet support <template> elements at the time of writing), use the following method. It's the same thing the libraries use to do to get DOM elements from an HTML string (with some extra work for IE to work around bugs with its implementation of innerHTML):

function createElementFromHTML(htmlString) {
  var div = document.createElement('div');
  div.innerHTML = htmlString.trim();

  // Change this to div.childNodes to support multiple top-level nodes.
  return div.firstChild;
}

Note that unlike HTML templates this won't work for some elements that cannot legally be children of a <div>, such as <td>s.

If you're already using a library, I would recommend you stick to the library-approved method of creating elements from HTML strings:

Upvotes: 1118

Raza
Raza

Reputation: 3403

I added a Document prototype that creates an element from string:

Document.prototype.createElementFromString = function (str) {
   const element = new DOMParser().parseFromString(str, 'text/html');
   const child = element.documentElement.querySelector('body').firstChild;
   return child;
};

Usage:

document.createElementFromString("<h1>Hello World!</h1>");

Upvotes: 11

Farhan
Farhan

Reputation: 1505

I have searched a lot for this myself and came across this solution which is neat.

const stringToHTML = (str) => {
    var parser = new DOMParser();
    var doc = parser.parseFromString(str, 'text/html');
    return doc.body;
};

String that I wanted to convert:

'<iframe src="https://player.vimeo.com/video/578680903?h=ea840f9223&amp;app_id=122963" width="640" height="360" frameborder="0" allow="autoplay; fullscreen; picture-in-picture" allowfullscreen title="Total Body Balance"></iframe>'

The result:

<body><iframe src="https://player.vimeo.com/video/578680903?h=ea840f9223&amp;app_id=122963" width="640" height="360" frameborder="0" allow="autoplay; fullscreen; picture-in-picture" allowfullscreen="" title="Total Body Balance"></iframe></body>

Upvotes: 2

Pablo Borowicz
Pablo Borowicz

Reputation: 921

Here's how to do it with PrototypeJS (as originally requested by the OP 12 years ago):

HTML:

<ul id="mylist"></ul>

JS:

$('mylist').insert('<li>text</li>');

Note that this is not jQuery!

Upvotes: 4

Munawwar
Munawwar

Reputation: 1862

For certain html fragments like <td>test</td>, div.innerHTML, DOMParser.parseFromString and range.createContextualFragment (without the right context) solutions mentioned in other answers here, won't create the <td> element.

jQuery.parseHTML() handles them properly (I extracted jQuery 2's parseHTML function into an independent function that can be used in non-jquery codebases).

If you are only supporting Edge 13+, it is simpler to just use the HTML5 template tag:

function parseHTML(html) {
    var t = document.createElement('template');
    t.innerHTML = html;
    return t.content;
}

var documentFragment = parseHTML('<td>Test</td>');

Upvotes: 47

Carson
Carson

Reputation: 8138

I've linked from this article.( Converting HTML string into DOM elements? )

For me, I want to find a way to convert a string into an HTML element. If you also have this need, you can try the following

const frag = document.createRange().createContextualFragment(
`<a href="/link.js">js</a> 
 <a>go</a>
`
) 
const aCollection = frag.querySelectorAll("a")
for (let [key, a] of Object.entries(aCollection)) {
  console.log(a.getAttribute("href"), a.textContent)
}

Upvotes: -1

Sam Saarian
Sam Saarian

Reputation: 1146

Why don't do with native js?

    var s="<span class='text-muted' style='font-size:.75em; position:absolute; bottom:3px; left:30px'>From <strong>Dan's Tools</strong></span>"
    var e=document.createElement('div')
    var r=document.createRange();
    r.selectNodeContents(e)
    var f=r.createContextualFragment(s);
    e.appendChild(f);
    e = e.firstElementChild;

Upvotes: 8

Monwell Partee
Monwell Partee

Reputation: 718

Answer

  • Create a Template
  • Set the Template's innerHTML to your string .trim()
  • Create an Array of Template's children
  • Return children, child, or 

function toElement(s='',c,t=document.createElement('template'),l='length'){
t.innerHTML=s.trim();c=[...t.content.childNodes];return c[l]>1?c:c[0]||'';}



console.log(toElement());
console.log(toElement(''));
console.log(toElement('    '));
console.log(toElement('<td>With td</td>'));
console.log(toElement('<tr><td>With t</td></tr>'));
console.log(toElement('<tr><td>foo</td></tr><tr><td>bar</td></tr>'));
console.log(toElement('<div><span>nested</span> <span>stuff</span></div>'));

Upvotes: 6

Mathieu Paturel
Mathieu Paturel

Reputation: 4510

No need for any tweak, you got a native API:

const toNodes = html =>
    new DOMParser().parseFromString(html, 'text/html').body.childNodes[0]

Upvotes: 52

Paweł Kołodziejczak
Paweł Kołodziejczak

Reputation: 31

Fastest solution to render DOM from string:

let render = (relEl, tpl, parse = true) => {
  if (!relEl) return;
  const range = document.createRange();
  range.selectNode(relEl);
  const child = range.createContextualFragment(tpl);
  return parse ? relEl.appendChild(child) : {relEl, el};
};

And here u can check performance for DOM manipulation React vs native JS

Now u can simply use:

let element = render(document.body, `
<div style="font-size:120%;line-height:140%">
  <p class="bold">New DOM</p>
</div>
`);

And of course in near future u use references from memory cause var "element" is your new created DOM in your document.

And remember "innerHTML=" is very slow :/

Upvotes: 3

nitish kumar
nitish kumar

Reputation: 151

var msg = "test" jQuery.parseHTML(msg)

Upvotes: -3

user8629798
user8629798

Reputation:

HTML5 & ES6

<template>

Demo

"use strict";

/**
 *
 * @author xgqfrms
 * @license MIT
 * @copyright xgqfrms
 * @description HTML5 Template
 * @augments
 * @example
 *
 */

/*

<template>
    <h2>Flower</h2>
    <img src="https://www.w3schools.com/tags/img_white_flower.jpg">
</template>


<template>
    <div class="myClass">I like: </div>
</template>

*/

const showContent = () => {
    // let temp = document.getElementsByTagName("template")[0],
    let temp = document.querySelector(`[data-tempalte="tempalte-img"]`),
        clone = temp.content.cloneNode(true);
    document.body.appendChild(clone);
};

const templateGenerator = (datas = [], debug = false) => {
    let result = ``;
    // let temp = document.getElementsByTagName("template")[1],
    let temp = document.querySelector(`[data-tempalte="tempalte-links"]`),
        item = temp.content.querySelector("div");
    for (let i = 0; i < datas.length; i++) {
        let a = document.importNode(item, true);
        a.textContent += datas[i];
        document.body.appendChild(a);
    }
    return result;
};

const arr = ["Audi", "BMW", "Ford", "Honda", "Jaguar", "Nissan"];

if (document.createElement("template").content) {
    console.log("YES! The browser supports the template element");
    templateGenerator(arr);
    setTimeout(() => {
        showContent();
    }, 0);
} else {
    console.error("No! The browser does not support the template element");
}
@charset "UTf-8";

/* test.css */

:root {
    --cololr: #000;
    --default-cololr: #fff;
    --new-cololr: #0f0;
}

[data-class="links"] {
    color: white;
    background-color: DodgerBlue;
    padding: 20px;
    text-align: center;
    margin: 10px;
}
<!DOCTYPE html>
<html lang="zh-Hans">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Template Test</title>
    <!--[if lt IE 9]>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/html5shiv/3.7.3/html5shiv.js"></script>
    <![endif]-->
</head>

<body>
    <section>
        <h1>Template Test</h1>
    </section>
    <template data-tempalte="tempalte-img">
        <h3>Flower Image</h3>
        <img src="https://www.w3schools.com/tags/img_white_flower.jpg">
    </template>
    <template data-tempalte="tempalte-links">
        <h3>links</h3>
        <div data-class="links">I like: </div>
    </template>
    <!-- js -->
</body>

</html>

Upvotes: 4

Christian d&#39;Heureuse
Christian d&#39;Heureuse

Reputation: 5630

Use insertAdjacentHTML(). It works with all current browsers, even with IE11.

var mylist = document.getElementById('mylist');
mylist.insertAdjacentHTML('beforeend', '<li>third</li>');
<ul id="mylist">
 <li>first</li>
 <li>second</li>
</ul>

Upvotes: 265

Sandeep Badawe
Sandeep Badawe

Reputation: 1

Here is working code for me

I wanted to convert 'Text' string to HTML element

var diva = UWA.createElement('div');
diva.innerHTML = '<a href="http://wwww.example.com">Text</a>';
var aelement = diva.firstChild;

Upvotes: -3

Saeed saeeyd
Saeed saeeyd

Reputation: 19

You can use the following function to convert the text "HTML" to the element

function htmlToElement(html)
{
  var element = document.createElement('div');
  element.innerHTML = html;
  return(element);
}
var html="<li>text and html</li>";
var e=htmlToElement(html);

Upvotes: -2

kojiro
kojiro

Reputation: 77167

Newer DOM implementations have range.createContextualFragment, which does what you want in a framework-independent way.

It's widely supported. To be sure though, check its compatibility down in the same MDN link, as it will be changing. As of May 2017 this is it:

Feature         Chrome   Edge   Firefox(Gecko)  Internet Explorer   Opera   Safari
Basic support   (Yes)    (Yes)  (Yes)           11                  15.0    9.1.2

Upvotes: 34

GibboK
GibboK

Reputation: 73988

You can create valid DOM nodes from a string using:

document.createRange().createContextualFragment()

The following example adds a button element in the page taking the markup from a string:

let html = '<button type="button">Click Me!</button>';
let fragmentFromString = function (strHTML) {
  return document.createRange().createContextualFragment(strHTML);
}
let fragment = fragmentFromString(html);
document.body.appendChild(fragment);

Upvotes: 17

usrbowe
usrbowe

Reputation: 539

I am using this method (Works in IE9+), although it will not parse <td> or some other invalid direct childs of body:

function stringToEl(string) {
    var parser = new DOMParser(),
        content = 'text/html',
        DOM = parser.parseFromString(string, content);

    // return element
    return DOM.body.childNodes[0];
}

stringToEl('<li>text</li>'); //OUTPUT: <li>text</li>

Upvotes: 11

Denim Demon
Denim Demon

Reputation: 734

function domify (str) {
  var el = document.createElement('div');
  el.innerHTML = str;

  var frag = document.createDocumentFragment();
  return frag.appendChild(el.removeChild(el.firstChild));
}

var str = "<div class='foo'>foo</div>";
domify(str);

Upvotes: -1

JxAxMxIxN
JxAxMxIxN

Reputation: 1731

For the heck of it I thought I'd share this over complicated but yet simple approach I came up with... Maybe someone will find something useful.

/*Creates a new element - By Jamin Szczesny*/
function _new(args){
    ele = document.createElement(args.node);
    delete args.node;
    for(x in args){ 
        if(typeof ele[x]==='string'){
            ele[x] = args[x];
        }else{
            ele.setAttribute(x, args[x]);
        }
    }
    return ele;
}

/*You would 'simply' use it like this*/

$('body')[0].appendChild(_new({
    node:'div',
    id:'my-div',
    style:'position:absolute; left:100px; top:100px;'+
          'width:100px; height:100px; border:2px solid red;'+
          'cursor:pointer; background-color:HoneyDew',
    innerHTML:'My newly created div element!',
    value:'for example only',
    onclick:"alert('yay')"
}));

Upvotes: 1

william malo
william malo

Reputation: 2506

Heres a simple way to do it:

String.prototype.toDOM=function(){
  var d=document
     ,i
     ,a=d.createElement("div")
     ,b=d.createDocumentFragment();
  a.innerHTML=this;
  while(i=a.firstChild)b.appendChild(i);
  return b;
};

var foo="<img src='//placekitten.com/100/100'>foo<i>bar</i>".toDOM();
document.body.appendChild(foo);

Upvotes: 17

Kerem
Kerem

Reputation: 11586

Late but just as a note;

It's possible to add a trivial element to target element as a container and remove it after using.

// Tested on chrome 23.0, firefox 18.0, ie 7-8-9 and opera 12.11.

<div id="div"></div>

<script>
window.onload = function() {
    var foo, targetElement = document.getElementById('div')
    foo = document.createElement('foo')
    foo.innerHTML = '<a href="#" target="_self">Text of A 1.</a> '+
                    '<a href="#" onclick="return !!alert(this.innerHTML)">Text of <b>A 2</b>.</a> '+
                    '<hr size="1" />'
    // Append 'foo' element to target element
    targetElement.appendChild(foo)

    // Add event
    foo.firstChild.onclick = function() { return !!alert(this.target) }

    while (foo.firstChild) {
        // Also removes child nodes from 'foo'
        targetElement.insertBefore(foo.firstChild, foo)
    }
    // Remove 'foo' element from target element
    targetElement.removeChild(foo)
}
</script>

Upvotes: 3

Berezh
Berezh

Reputation: 937

var jtag = $j.li({ child:'text' }); // Represents: <li>text</li>
var htmlContent = $('mylist').html();
$('mylist').html(htmlContent + jtag.html());

Use jnerator

Upvotes: -4

jack
jack

Reputation: 731

This will work too:

$('<li>').text('hello').appendTo('#mylist');

It feels more like a jquery way with the chained function calls.

Upvotes: -9

Wen Qi
Wen Qi

Reputation: 663

Here's my code, and it works:

function parseTableHtml(s) { // s is string
    var div = document.createElement('table');
    div.innerHTML = s;

    var tr = div.getElementsByTagName('tr');
    // ...
}

Upvotes: 2

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