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Get words length from html string [duplicate]

Is there an easy way to take a string of html in JavaScript and strip out the html?

If you're running in a browser, then the easiest way is just to let the browser do it for you...
function stripHtml(html)
{
let tmp = document.createElement("DIV");
tmp.innerHTML = html;
return tmp.textContent || tmp.innerText || "";
}
Note: as folks have noted in the comments, this is best avoided if you don't control the source of the HTML (for example, don't run this on anything that could've come from user input). For those scenarios, you can still let the browser do the work for you - see Saba's answer on using the now widely-available DOMParser.

myString.replace(/<[^>]*>?/gm, '');

Simplest way:
jQuery(html).text();
That retrieves all the text from a string of html.

I would like to share an edited version of the Shog9's approved answer.
As Mike Samuel pointed with a comment, that function can execute inline javascript code.
But Shog9 is right when saying "let the browser do it for you..."
so.. here my edited version, using DOMParser:
function strip(html){
let doc = new DOMParser().parseFromString(html, 'text/html');
return doc.body.textContent || "";
}
here the code to test the inline javascript:
strip("<img onerror='alert(\"could run arbitrary JS here\")' src=bogus>")
Also, it does not request resources on parse (like images)
strip("Just text <img src='https://assets.rbl.ms/4155638/980x.jpg'>")

As an extension to the jQuery method, if your string might not contain HTML (eg if you are trying to remove HTML from a form field)
jQuery(html).text();
will return an empty string if there is no HTML
Use:
jQuery('<p>' + html + '</p>').text();
instead.
Update:
As has been pointed out in the comments, in some circumstances this solution will execute javascript contained within html if the value of html could be influenced by an attacker, use a different solution.

Converting HTML for Plain Text emailing keeping hyperlinks (a href) intact
The above function posted by hypoxide works fine, but I was after something that would basically convert HTML created in a Web RichText editor (for example FCKEditor) and clear out all HTML but leave all the Links due the fact that I wanted both the HTML and the plain text version to aid creating the correct parts to an STMP email (both HTML and plain text).
After a long time of searching Google myself and my collegues came up with this using the regex engine in Javascript:
str='this string has <i>html</i> code i want to <b>remove</b><br>Link Number 1 ->BBC Link Number 1<br><p>Now back to normal text and stuff</p>
';
str=str.replace(/<br>/gi, "\n");
str=str.replace(/<p.*>/gi, "\n");
str=str.replace(/<a.*href="(.*?)".*>(.*?)<\/a>/gi, " $2 (Link->$1) ");
str=str.replace(/<(?:.|\s)*?>/g, "");
the str variable starts out like this:
this string has <i>html</i> code i want to <b>remove</b><br>Link Number 1 ->BBC Link Number 1<br><p>Now back to normal text and stuff</p>
and then after the code has run it looks like this:-
this string has html code i want to remove
Link Number 1 -> BBC (Link->http://www.bbc.co.uk) Link Number 1
Now back to normal text and stuff
As you can see the all the HTML has been removed and the Link have been persevered with the hyperlinked text is still intact. Also I have replaced the <p> and <br> tags with \n (newline char) so that some sort of visual formatting has been retained.
To change the link format (eg. BBC (Link->http://www.bbc.co.uk) ) just edit the $2 (Link->$1), where $1 is the href URL/URI and the $2 is the hyperlinked text. With the links directly in body of the plain text most SMTP Mail Clients convert these so the user has the ability to click on them.
Hope you find this useful.

An improvement to the accepted answer.
function strip(html)
{
var tmp = document.implementation.createHTMLDocument("New").body;
tmp.innerHTML = html;
return tmp.textContent || tmp.innerText || "";
}
This way something running like this will do no harm:
strip("<img onerror='alert(\"could run arbitrary JS here\")' src=bogus>")
Firefox, Chromium and Explorer 9+ are safe.
Opera Presto is still vulnerable.
Also images mentioned in the strings are not downloaded in Chromium and Firefox saving http requests.

This should do the work on any Javascript environment (NodeJS included).
const text = `
<html lang="en">
<head>
<style type="text/css">*{color:red}</style>
<script>alert('hello')</script>
</head>
<body><b>This is some text</b><br/><body>
</html>`;
// Remove style tags and content
text.replace(/<style[^>]*>.*<\/style>/gm, '')
// Remove script tags and content
.replace(/<script[^>]*>.*<\/script>/gm, '')
// Remove all opening, closing and orphan HTML tags
.replace(/<[^>]+>/gm, '')
// Remove leading spaces and repeated CR/LF
.replace(/([\r\n]+ +)+/gm, '');

I altered Jibberboy2000's answer to include several <BR /> tag formats, remove everything inside <SCRIPT> and <STYLE> tags, format the resulting HTML by removing multiple line breaks and spaces and convert some HTML-encoded code into normal. After some testing it appears that you can convert most of full web pages into simple text where page title and content are retained.
In the simple example,
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<!--comment-->
<head>
<title>This is my title</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style>
body {margin-top: 15px;}
a { color: #D80C1F; font-weight:bold; text-decoration:none; }
</style>
</head>
<body>
<center>
This string has <i>html</i> code i want to <b>remove</b><br>
In this line BBC with link is mentioned.<br/>Now back to "normal text" and stuff using <html encoding>
</center>
</body>
</html>
becomes
This is my title
This string has html code i want to remove
In this line BBC (http://www.bbc.co.uk) with link is mentioned.
Now back to "normal text" and stuff using
The JavaScript function and test page look this:
function convertHtmlToText() {
var inputText = document.getElementById("input").value;
var returnText = "" + inputText;
//-- remove BR tags and replace them with line break
returnText=returnText.replace(/<br>/gi, "\n");
returnText=returnText.replace(/<br\s\/>/gi, "\n");
returnText=returnText.replace(/<br\/>/gi, "\n");
//-- remove P and A tags but preserve what's inside of them
returnText=returnText.replace(/<p.*>/gi, "\n");
returnText=returnText.replace(/<a.*href="(.*?)".*>(.*?)<\/a>/gi, " $2 ($1)");
//-- remove all inside SCRIPT and STYLE tags
returnText=returnText.replace(/<script.*>[\w\W]{1,}(.*?)[\w\W]{1,}<\/script>/gi, "");
returnText=returnText.replace(/<style.*>[\w\W]{1,}(.*?)[\w\W]{1,}<\/style>/gi, "");
//-- remove all else
returnText=returnText.replace(/<(?:.|\s)*?>/g, "");
//-- get rid of more than 2 multiple line breaks:
returnText=returnText.replace(/(?:(?:\r\n|\r|\n)\s*){2,}/gim, "\n\n");
//-- get rid of more than 2 spaces:
returnText = returnText.replace(/ +(?= )/g,'');
//-- get rid of html-encoded characters:
returnText=returnText.replace(/ /gi," ");
returnText=returnText.replace(/&/gi,"&");
returnText=returnText.replace(/"/gi,'"');
returnText=returnText.replace(/</gi,'<');
returnText=returnText.replace(/>/gi,'>');
//-- return
document.getElementById("output").value = returnText;
}
It was used with this HTML:
<textarea id="input" style="width: 400px; height: 300px;"></textarea><br />
<button onclick="convertHtmlToText()">CONVERT</button><br />
<textarea id="output" style="width: 400px; height: 300px;"></textarea><br />

var text = html.replace(/<\/?("[^"]*"|'[^']*'|[^>])*(>|$)/g, "");
This is a regex version, which is more resilient to malformed HTML, like:
Unclosed tags
Some text <img
"<", ">" inside tag attributes
Some text <img alt="x > y">
Newlines
Some <a
href="http://google.com">
The code
var html = '<br>This <img alt="a>b" \r\n src="a_b.gif" />is > \nmy<>< > <a>"text"</a'
var text = html.replace(/<\/?("[^"]*"|'[^']*'|[^>])*(>|$)/g, "");

from CSS tricks:
https://css-tricks.com/snippets/javascript/strip-html-tags-in-javascript/
const originalString = `
<div>
<p>Hey that's <span>somthing</span></p>
</div>
`;
const strippedString = originalString.replace(/(<([^>]+)>)/gi, "");
console.log(strippedString);

Another, admittedly less elegant solution than nickf's or Shog9's, would be to recursively walk the DOM starting at the <body> tag and append each text node.
var bodyContent = document.getElementsByTagName('body')[0];
var result = appendTextNodes(bodyContent);
function appendTextNodes(element) {
var text = '';
// Loop through the childNodes of the passed in element
for (var i = 0, len = element.childNodes.length; i < len; i++) {
// Get a reference to the current child
var node = element.childNodes[i];
// Append the node's value if it's a text node
if (node.nodeType == 3) {
text += node.nodeValue;
}
// Recurse through the node's children, if there are any
if (node.childNodes.length > 0) {
appendTextNodes(node);
}
}
// Return the final result
return text;
}

If you want to keep the links and the structure of the content (h1, h2, etc) then you should check out TextVersionJS You can use it with any HTML, although it was created to convert an HTML email to plain text.
The usage is very simple. For example in node.js:
var createTextVersion = require("textversionjs");
var yourHtml = "<h1>Your HTML</h1><ul><li>goes</li><li>here.</li></ul>";
var textVersion = createTextVersion(yourHtml);
Or in the browser with pure js:
<script src="textversion.js"></script>
<script>
var yourHtml = "<h1>Your HTML</h1><ul><li>goes</li><li>here.</li></ul>";
var textVersion = createTextVersion(yourHtml);
</script>
It also works with require.js:
define(["textversionjs"], function(createTextVersion) {
var yourHtml = "<h1>Your HTML</h1><ul><li>goes</li><li>here.</li></ul>";
var textVersion = createTextVersion(yourHtml);
});

const htmlParser= new DOMParser().parseFromString("<h6>User<p>name</p></h6>" , 'text/html');
const textString= htmlParser.body.textContent;
console.log(textString)

A lot of people have answered this already, but I thought it might be useful to share the function I wrote that strips HTML tags from a string but allows you to include an array of tags that you do not want stripped. It's pretty short and has been working nicely for me.
function removeTags(string, array){
return array ? string.split("<").filter(function(val){ return f(array, val); }).map(function(val){ return f(array, val); }).join("") : string.split("<").map(function(d){ return d.split(">").pop(); }).join("");
function f(array, value){
return array.map(function(d){ return value.includes(d + ">"); }).indexOf(true) != -1 ? "<" + value : value.split(">")[1];
}
}
var x = "<span><i>Hello</i> <b>world</b>!</span>";
console.log(removeTags(x)); // Hello world!
console.log(removeTags(x, ["span", "i"])); // <span><i>Hello</i> world!</span>

For easier solution, try this => https://css-tricks.com/snippets/javascript/strip-html-tags-in-javascript/
var StrippedString = OriginalString.replace(/(<([^>]+)>)/ig,"");

It is also possible to use the fantastic htmlparser2 pure JS HTML parser. Here is a working demo:
var htmlparser = require('htmlparser2');
var body = '<p><div>This is </div>a <span>simple </span> <img src="test"></img>example.</p>';
var result = [];
var parser = new htmlparser.Parser({
ontext: function(text){
result.push(text);
}
}, {decodeEntities: true});
parser.write(body);
parser.end();
result.join('');
The output will be This is a simple example.
See it in action here: https://tonicdev.com/jfahrenkrug/extract-text-from-html
This works in both node and the browser if you pack your web application using a tool like webpack.

I made some modifications to original Jibberboy2000 script
Hope it'll be usefull for someone
str = '**ANY HTML CONTENT HERE**';
str=str.replace(/<\s*br\/*>/gi, "\n");
str=str.replace(/<\s*a.*href="(.*?)".*>(.*?)<\/a>/gi, " $2 (Link->$1) ");
str=str.replace(/<\s*\/*.+?>/ig, "\n");
str=str.replace(/ {2,}/gi, " ");
str=str.replace(/\n+\s*/gi, "\n\n");

After trying all of the answers mentioned most if not all of them had edge cases and couldn't completely support my needs.
I started exploring how php does it and came across the php.js lib which replicates the strip_tags method here: http://phpjs.org/functions/strip_tags/

function stripHTML(my_string){
var charArr = my_string.split(''),
resultArr = [],
htmlZone = 0,
quoteZone = 0;
for( x=0; x < charArr.length; x++ ){
switch( charArr[x] + htmlZone + quoteZone ){
case "<00" : htmlZone = 1;break;
case ">10" : htmlZone = 0;resultArr.push(' ');break;
case '"10' : quoteZone = 1;break;
case "'10" : quoteZone = 2;break;
case '"11' :
case "'12" : quoteZone = 0;break;
default : if(!htmlZone){ resultArr.push(charArr[x]); }
}
}
return resultArr.join('');
}
Accounts for > inside attributes and <img onerror="javascript"> in newly created dom elements.
usage:
clean_string = stripHTML("string with <html> in it")
demo:
https://jsfiddle.net/gaby_de_wilde/pqayphzd/
demo of top answer doing the terrible things:
https://jsfiddle.net/gaby_de_wilde/6f0jymL6/1/

Here's a version which sorta addresses #MikeSamuel's security concern:
function strip(html)
{
try {
var doc = document.implementation.createDocument('http://www.w3.org/1999/xhtml', 'html', null);
doc.documentElement.innerHTML = html;
return doc.documentElement.textContent||doc.documentElement.innerText;
} catch(e) {
return "";
}
}
Note, it will return an empty string if the HTML markup isn't valid XML (aka, tags must be closed and attributes must be quoted). This isn't ideal, but does avoid the issue of having the security exploit potential.
If not having valid XML markup is a requirement for you, you could try using:
var doc = document.implementation.createHTMLDocument("");
but that isn't a perfect solution either for other reasons.

I think the easiest way is to just use Regular Expressions as someone mentioned above. Although there's no reason to use a bunch of them. Try:
stringWithHTML = stringWithHTML.replace(/<\/?[a-z][a-z0-9]*[^<>]*>/ig, "");

Below code allows you to retain some html tags while stripping all others
function strip_tags(input, allowed) {
allowed = (((allowed || '') + '')
.toLowerCase()
.match(/<[a-z][a-z0-9]*>/g) || [])
.join(''); // making sure the allowed arg is a string containing only tags in lowercase (<a><b><c>)
var tags = /<\/?([a-z][a-z0-9]*)\b[^>]*>/gi,
commentsAndPhpTags = /<!--[\s\S]*?-->|<\?(?:php)?[\s\S]*?\?>/gi;
return input.replace(commentsAndPhpTags, '')
.replace(tags, function($0, $1) {
return allowed.indexOf('<' + $1.toLowerCase() + '>') > -1 ? $0 : '';
});
}

I just needed to strip out the <a> tags and replace them with the text of the link.
This seems to work great.
htmlContent= htmlContent.replace(/<a.*href="(.*?)">/g, '');
htmlContent= htmlContent.replace(/<\/a>/g, '');

The accepted answer works fine mostly, however in IE if the html string is null you get the "null" (instead of ''). Fixed:
function strip(html)
{
if (html == null) return "";
var tmp = document.createElement("DIV");
tmp.innerHTML = html;
return tmp.textContent || tmp.innerText || "";
}

A safer way to strip the html with jQuery is to first use jQuery.parseHTML to create a DOM, ignoring any scripts, before letting jQuery build an element and then retrieving only the text.
function stripHtml(unsafe) {
return $($.parseHTML(unsafe)).text();
}
Can safely strip html from:
<img src="unknown.gif" onerror="console.log('running injections');">
And other exploits.
nJoy!

const strip=(text) =>{
return (new DOMParser()?.parseFromString(text,"text/html"))
?.body?.textContent
}
const value=document.getElementById("idOfEl").value
const cleanText=strip(value)

With jQuery you can simply retrieving it by using
$('#elementID').text()

I have created a working regular expression myself:
str=str.replace(/(<\?[a-z]*(\s[^>]*)?\?(>|$)|<!\[[a-z]*\[|\]\]>|<!DOCTYPE[^>]*?(>|$)|<!--[\s\S]*?(-->|$)|<[a-z?!\/]([a-z0-9_:.])*(\s[^>]*)?(>|$))/gi, '');

simple 2 line jquery to strip the html.
var content = "<p>checking the html source </p><p>
</p><p>with </p><p>all</p><p>the html </p><p>content</p>";
var text = $(content).text();//It gets you the plain text
console.log(text);//check the data in your console
cj("#text_area_id").val(text);//set your content to text area using text_area_id

New to Javascript, could someone help me with this substring problem?

The below script returns the following into my html:
"3.9 °C {alarm,unackedAlarm}"
I would like to remove the "{alarm,unackedAlarm}" section so it just shows the temperature value. I believe I need to use a substring to achieve this but I cannot work out where to place it?
Thanks
<script src="https://requirejs.org/docs/release/2.3.6/minified/require.js" ></script>
require(['baja!', 'dialogs'], function (baja, dialogs) {
var sub = new baja.Subscriber();
sub.attach('changed', function(prop) {
if(prop.getName() === 'value');
{
document.getElementById("oat").innerHTML = ( this.get(prop));
}
});
baja.Ord.make('station:|slot:/BajaScriptExamples/Components/Ramp/out/value').get({ subscriber: sub});
});
'''

I would suggest using the regex approach just in case the number of characters change.
function extract(text) {
const pattern = /^(.*) {.*}$/g;
const match = [...text.matchAll(pattern)];
if (match.length == 0 || match[0].length == 0) {
console.error("text does not match");
return;
}
return match[0][1];
}
console.log(extract("3.9 °C {alarm,unackedAlarm}"));
The main idea here is to catch any string that follows this pattern (.*) {.*} and return what is in contained between the parenthesis (group).

The requirement of extracting specific part of a string can be done easily by using the split() function of Javascript.
Here are working examples using split:
Example 1: Split the string at blank spaces and print the first two parts.
<!DOCTYPE html>
<html>
<body>
<p id="demo"></p>
<script>
var str = "3.9 °C {alarm,unackedAlarm}"
var result = str.split(" ")
document.getElementById("demo").innerHTML = (result[0] + " " + result[1])
</script>
</body>
</html>
Example 2: Split the string at '{' and print the first part.
<!DOCTYPE html>
<html>
<body>
<p id="demo"></p>
<script>
var str = "3.9 °C {alarm,unackedAlarm}"
var result = str.split("{")
document.getElementById("demo").innerHTML = (result[0].trim())
</script>
</body>
</html>
Output:
3.9 °C
More information:
https://www.w3schools.com/jsref/jsref_split.asp

Javascript library to compare 2 html string like freecodecamp

I have a project where we have a compare the original code and code written by the user. The user can code and then on button click we have to compare the written code with original code.
I have both original and new code in string
originalHtml : <html><body style='color:white;background:purple;'></body></html>
newHtml : <html> <body style="background:purple;color:white;"> </body> . </html>
Here there are 3 things to keep in mind
1) White space (should not show the difference for white space)
2) ' and " (should not compare quotes, both are valid in HTML)
3) Attribute order (should show difference only for missing attribute, ignore attributes order)
Any suggestions or alternative solution will be appreciated.

I have created a code pen for you, this will solve your problem.
https://codepen.io/bearnithi/pen/KEPXrX
const textArea = document.getElementById('code');
const btn = document.getElementById('checkcode');
const result = document.getElementById('result');
let originalHTML = `<html><head>
<title>Hello </title>
</head><body>
<p class="hello"></p>
</body>
</html>`
btn.addEventListener('click', checkCode);
function checkCode() {
let newHTMLCode = textArea.value.replace(/\s/g,"");
let oldHTMLCode = originalHTML.replace(/\s/g,"");
if(newHTMLCode === oldHTMLCode) {
console.log(true);
result.innerHTML = 'TRUE';
} else {
console.log(false);
result.innerHTML = 'FALSE';
}
}
<textarea id="code">
</textarea>
</br>
<button id="checkcode">Check Code</button>
<p id="result"></p>

You can convert all of them to one uniform and compare them.
Example:
remove all space, tab (with one space)
replace all ' to "
sort attribute.
and some rule you defined
Example cheerio to get attribute:
var cheerio = require('cheerio');
var yourString = `<html><body attr2='hi' attr1='hello' style='color:white;background:purple;'></body></html>`;
var $ = cheerio.load(yourString);
var yourAttrs = $('body')[0].attribs;
var sorted = {};
Object.keys(yourAttrs).sort().forEach(function(key) {
sorted[key] = yourAttrs[key];
});
console.log(sorted);

How to write the code in "function printOut(){} " in javascript?

I need help with how to code this program in javascript. The javascript code should load a character from a box and a number (N) from another box. When you press a button, N rows prints each one of those with N characters (same characters that are loaded are printed). Before printing, check that it is only available a character in the box where characters are to be entered.
code in html:
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<p id="theText"></p>
<p id="theNumber"></p>
a charachter: <input type="charachter" id="theChar">
a number: <input type="number" id="theNbr">
<button onclick="printOut()">print out!</button>
<script type="text/javascript" src="script.js" ></script>
</body>
</html>
Code in Javascript:
function printOut(){
var theText = document.getElementById("theText").innerHTML;
document.getElementById("theText").innerHTML=
document.getElementById("theChar").value;
var theNumber = document.getElementById("theNbr").innerHTML;
document.getElementById("theNumber").innerHTML=
document.getElementById("theNbr").value;
var newText= theText;
var outPut;
for(i = 0; i<theNumber; i++){
newText =newText + theText;
}
newText = newText + "<br>";
for( i = 0; i< theNumber; i++){
outPut = outPut + newText;
}
document.getElementById("theText").innerHTML= outPut;
}

There are several issues in your code, even after the corrections you made after comments were made. Some of the more important:
Don't use innerHTML on an input element. It makes no sense. To get its value, use value.
Don't assign to document.getElementById("theNumber").innerHTML: it will replace any HTML you already had, and thus will remove the theNbr input. Any reference to it will fail with an error from now on.
Initialise your variables before reading from them. outPut is never initialised and so outPut + newText will give undesired results.
Although your can do this with for loops, there is a nice string method in JavaScript with which you can repeat a character or even a longer string: repeat.
Here is how it could work:
function printOut(){
var theNumber = document.getElementById("theNbr").value; // Don't use innerHTML
var theChar = document.getElementById("theChar").value;
var oneLine = theChar.repeat(theNumber) + "<br>";
var output = oneLine.repeat(theNumber);
document.getElementById("theText").innerHTML = output;
}
a charachter: <input type="charachter" id="theChar">
a number: <input type="number" id="theNbr">
<button onclick="printOut()">print out!</button>
<p id="theText"></p>

Make HTML text bold

I wrote this function which takes in a word as input and puts it in a <b> tag so that it would be bold when rendered in HTML. But when it actually does get rendered, the word is not bold, but only has the <b> tag arround it.
Here is the function:
function delimiter(input, value) {
return input.replace(new RegExp('(\\b)(' + value + ')(\\b)','ig'), '$1<b>$2</b>$3');
}
On providing the value and input, e.g. "message" and "This is a test message":
The output is: This is a test <b>message</b>
The desired output is: This is a test message
Even replacing the value with value.bold(), returns the same thing.
EDIT
This is the HTML together with the JS that I m working on:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
<title>Test</title>
<script>
function myFunction(){
var children = document.body.childNodes;
for(var len = children.length, child=0; child<len; child++){
if (children[child].nodeType === 3){ // textnode
var highLight = new Array('abcd', 'edge', 'rss feeds');
var contents = children[child].nodeValue;
var output = contents;
for(var i =0;i<highLight.length;i++){
output = delimiter(output, highLight[i]);
}
children[child].nodeValue= output;
}
}
}
function delimiter(input, value) {
return unescape(input.replace(new RegExp('(\\b)(' + value + ')(\\b)','ig'), '$1<b>$2</b>$3'));
}
</script>
</head>
<body>
<img src="http://some.web.site/image.jpg" title="knorex"/>
These words are highlighted: abcd, edge, rss feeds while these words are not: knewedge, abcdefgh, rss feedssss
<input type ="button" value="Button" onclick = "myFunction()">
</body>
</html>
I'm basically getting the result of the delimiter function and changing the nodeValue of a child node.
Is it possible there is something wrong with the way I'm taking back what the function is returning to me?
This is what I do:
children[child].nodeValue = output;

You need to have the markup processed as HTML, instead of being just set to replace existing content in a text node. For this, replace the statement
children[child].nodeValue= output;
by the following:
var newNode = document.createElement('span');
newNode.innerHTML = output;
document.body.replaceChild(newNode, children[child]);