Develop Reference

Why isn't there a document.createHTMLNode()?

I want to insert html at the current range (a W3C Range).
I guess i have to use the method insertNode. And it works great with text.
Example:
var node = document.createTextNode("some text");
range.insertNode(node);
The problem is that i want to insert html (might be something like "<h1>test</h1>some more text"). And there is no createHTMLNode().
I've tried to use createElement('div'), give it an id, and the html as innerHTML and then trying to replace it with it's nodeValue after inserting it but it gives me DOM Errors.
Is there a way to do this without getting an extra html-element around the html i want to insert?

Because "<h1>test</h1>some more text" consists of an HTML element and two pieces of text. It isn't a node.
If you want to insert HTML then use innerHTML.
Is there a way to do this without getting an extra html-element around the html i want to insert?
Create an element (don't add it to the document). Set its innerHTML. Then move all its child nodes by looping over foo.childNodes.

In some browsers (notably not any version of IE), Range objects have an originally non-standard createContextualFragment() that may help. It's likely that future versions of browsers such as IE will implement this now that it has been standardized.
Here's an example:
var frag = range.createContextualFragment("<h1>test</h1>some more text");
range.insertNode(frag);

Try
function createHTMLNode(htmlCode, tooltip) {
// create html node
var htmlNode = document.createElement('span');
htmlNode.innerHTML = htmlCode
htmlNode.className = 'treehtml';
htmlNode.setAttribute('title', tooltip);
return htmlNode;
}
From: http://www.koders.com/javascript/fid21CDC3EB9772B0A50EA149866133F0269A1D37FA.aspx

Instead of innerHTML just use appendChild(element); this may help you.
If you want comment here, and I will give you an example.

The Range.insertNode() method inserts a node at the start of the Range.
var range = window.getSelection().getRangeAt(0);
var node = document.createElement('b');
node.innerHTML = 'bold text';
range.insertNode(node);
Resources
https://developer.mozilla.org/en-US/docs/Web/API/range/insertNode

How to append text to '<textarea>'?

I have <textarea> where user can type in his message to the world! Below, there are upload buttons... I would love to add link to uploaded file (don't worry, I have it); right next to the text that he was typing in.
Like, he types in 'Hello, world!', then uploads the file (its done via AJAX), and the link to that file is added in next line to the content of <textarea>. Attention! Is it possible to keep cursor (place where he left to type) in the same place?
All that may be done with jQuery... Any ideas? I know that there are method 'append()', but it won't be for this situation, right?

Try
var myTextArea = $('#myTextarea');
myTextArea.val(myTextArea.val() + '\nYour appended stuff');

This took me a while, but the following jQuery will do exactly what you want -- it not only appends text, but also keeps the cursor in the exact same spot by storing it and then resetting it:
var selectionStart = $('#your_textarea')[0].selectionStart;
var selectionEnd = $('#your_textarea')[0].selectionEnd;
$('#your_textarea').val($('#your_textarea').val() + 'The text you want to append');
$('#your_textarea')[0].selectionStart = selectionStart;
$('#your_textarea')[0].selectionEnd = selectionEnd;
You should probably wrap this in a function though.

You may take a look at the following answer which presents a nice plugin for inserting text at the caret position in a <textarea>.

You can use any of the available caret plugins for jQuery and basically:
Store the current caret position
Append the text to the textarea
Use the plugin to replace the caret position
If you want an "append" function in jQuery, one is easy enough to make:
(function($){
$.fn.extend({
valAppend: function(text){
return this.each(function(i,e){
var $e = $(e);
$e.val($e.val() + text);
});
}
});
})(jQuery);
Then you can use it by making a call to .valAppend(), referencing the input field(s).

You could use my Rangy inputs jQuery plugin for this, which works in all major browsers.
var $textarea = $("your_textarea_id");
var sel = $textarea.getSelection();
$textarea.insertText("\nSome text", sel.end).setSelection(sel.start, sel.end);

javascript: extracting text from html

I am getting html content as below:
var test='<div id="test">Raj</div>';
How can i retrieve value Raj from above html content using javascript.

It sounds like you're trying to extract the text "Raj" from that HTML snippet?
To get the browser's HTML parser to do your dirty work for you:
// create an empty div
var div = document.createElement("div");
// fill it with your HTML
div.innerHTML = test;
// find the element whose text you want
test = div.getElementById("test");
// extract the text (innerText for IE, textContent for everyone else)
test = test.innerText || test.textContent;
Or in jQuery:
test = $(test).text();

If you use jQuery (I cannot believe I just said that ;)) you can get at the content immediately you wrap it in $(test).html
Someone else will tell you how to get at the innerHTML using a selector since everybody here are jQuery gurus but me
Update: somebody just did while I was editing: javascript: extracting text from html - see comments or updates to that

var test = getElementById('test')
try that

how to highlight part of textarea html code

I want to achieve a python version web regexbuddy,and i encounter a problem,how to highlight match values in different color(switch between yellow and blue) in a textarea,there has a demo what exactly i want on http://regexpal.com,but i was a newbie on js,i didn't understand his code meaning.
any advice is appreciated

To save time you should consider using an existing library for this requirement.
Quote from here:
As textarea elements can’t render HTML, this plugin allows you to highlight text inside textarea elements.
jQuery highlightTextarea.
Demo: Codepen
Usage:
$context.highlightTextarea(options);

There is a pre element over the textarea. So when you type anything it is copying the input on the pre element, applying some filters.
For example:
<pre id="view"></pre>
<textarea id="code"></textarea>
When you type on #code it is copying the value, applying filters and adding the HTML to the #view.
var code = document.getElementById("code");
var pre = document.getElementById("pre");
(code).onkeyup = function (){
val = this.value;
val = YourRegex(val);
(pre).innerHTML = val;
};
YourRegex would be a method to match the regex and return some parsed content to the pre, allowing you to customize the appearance of the textarea (that is actually an element over it).
function YourRegex(val)
{
// This function add colors, bold, whatever you want.
if (/bbcc/i.test("bbcc"))
return "<b>" + val + "</b>";
}

#BrunoLM's solution is excellent, but might require more hacking than you're comfortable with. If you're interested (and if jQuery is already in your stack), the following plugin may be worth taking a look at:
http://garysieling.github.io/jquery-highlighttextarea/

How do I change the text of a span element using JavaScript?

If I have a span, say:
<span id="myspan"> hereismytext </span>
How do I use JavaScript to change "hereismytext" to "newtext"?

For modern browsers you should use:
document.getElementById("myspan").textContent="newtext";
While older browsers may not know textContent, it is not recommended to use innerHTML as it introduces an XSS vulnerability when the new text is user input (see other answers below for a more detailed discussion):
//POSSIBLY INSECURE IF NEWTEXT BECOMES A VARIABLE!!
document.getElementById("myspan").innerHTML="newtext";

Using innerHTML is SO NOT RECOMMENDED.
Instead, you should create a textNode. This way, you are "binding" your text and you are not, at least in this case, vulnerable to an XSS attack.
document.getElementById("myspan").innerHTML = "sometext"; //INSECURE!!
The right way:
span = document.getElementById("myspan");
txt = document.createTextNode("your cool text");
span.appendChild(txt);
For more information about this vulnerability:
Cross Site Scripting (XSS) - OWASP
Edited nov 4th 2017:
Modified third line of code according to #mumush suggestion: "use appendChild(); instead".
Btw, according to #Jimbo Jonny I think everything should be treated as user input by applying Security by layers principle. That way you won't encounter any surprises.

EDIT: This was written in 2014. A lot has changed. You probably don't care about IE8 anymore. And Firefox now supports innerText.
If you are the one supplying the text and no part of the text is supplied by the user (or some other source that you don't control), then setting innerHTML might be acceptable:
// * Fine for hardcoded text strings like this one or strings you otherwise
// control.
// * Not OK for user-supplied input or strings you don't control unless
// you know what you are doing and have sanitized the string first.
document.getElementById('myspan').innerHTML = 'newtext';
However, as others note, if you are not the source for any part of the text string, using innerHTML can subject you to content injection attacks like XSS if you're not careful to properly sanitize the text first.
If you are using input from the user, here is one way to do it securely while also maintaining cross-browser compatibility:
var span = document.getElementById('myspan');
span.innerText = span.textContent = 'newtext';
Firefox doesn't support innerText and IE8 doesn't support textContent so you need to use both if you want to maintain cross-browser compatibility.
And if you want to avoid reflows (caused by innerText) where possible:
var span = document.getElementById('myspan');
if ('textContent' in span) {
span.textContent = 'newtext';
} else {
span.innerText = 'newtext';
}

document.getElementById('myspan').innerHTML = 'newtext';

I use Jquery and none of the above helped, I don't know why but this worked:
$("#span_id").text("new_value");

Here's another way:
var myspan = document.getElementById('myspan');
if (myspan.innerText) {
myspan.innerText = "newtext";
}
else
if (myspan.textContent) {
myspan.textContent = "newtext";
}
The innerText property will be detected by Safari, Google Chrome and MSIE. For Firefox, the standard way of doing things was to use textContent but since version 45 it too has an innerText property, as someone kindly apprised me recently. This solution tests to see if a browser supports either of these properties and if so, assigns the "newtext".
Live demo: here

In addition to the pure javascript answers above, You can use jQuery text method as following:
$('#myspan').text('newtext');
If you need to extend the answer to get/change html content of a span or div elements, you can do this:
$('#mydiv').html('<strong>new text</strong>');
References:
.text(): http://api.jquery.com/text/
.html(): http://api.jquery.com/html/

You may also use the querySelector() method, assuming the 'myspan' id is unique as the method returns the first element with the specified selector:
document.querySelector('#myspan').textContent = 'newtext';
developer.mozilla

Many people still come across this question (in 2022) and the available answers are not really up to date.
Use innerText is the best method
As you can see in the MDM Docs innerText is the best way to retrieve and change the text of a <span> HTML element via Javascript.
The innerText property is VERY well supported (97.53% of all web users according to Caniuse)
How to use
Simple retrieve and set new text with the property like this:
let mySpan = document.getElementById("myspan");
console.log(mySpan.innerText);
mySpan.innerText = "Setting a new text content into the span element.";
Why better than innerHTML ?
Don't use innerHTML to updating the content with user inputs, this can lead to major vulnerability since the string content you will set will be interpreted and converted into HTML tags.
This means users can insert script(s) into your site, this is known as XSS attacks/vulnerabilities (Cross-site scripting).
Why better than textContent ?
First point textContent isn't supported by IE8 (but I think in 2022 nobody cares anymore).
But the main element is the true difference of result you can get using textContent instead of innerText.
The example from the MDM documentation is perfect to illustrate that, so we have the following setup:
<p id="source">
<style>#source { color: red; } #text { text-transform: uppercase; }</style>
<span id=text>Take a look at<br>how this text<br>is interpreted
below.</span>
<span style="display:none">HIDDEN TEXT</span>
</p>
If you use innerText to retrieve the text content of <p id="source"> we get:
TAKE A LOOK AT
HOW THIS TEXT
IS INTERPRETED BELOW.
This is perfectly what we wanted.
Now using textContent we get:
#source { color: red; } #text { text-transform: uppercase; }
Take a look athow this textis interpreted
below.
HIDDEN TEXT
Not exactly what you expected...
This is why using textContent isn't the correct way.
Last point
If you goal is only to append text to a <p> or <span> HTML element, the answer from nicooo. is right you can create a new text node and append it to you existing element like this:
let mySpan = document.getElementById("myspan");
const newTextNode = document.createTextNode("Youhou!"),
mySpan.appendChild(newTextNode);

Like in other answer, innerHTML and innerText are not recommended, it's better use textContent. This attribute is well supported, you can check it this:
http://caniuse.com/#search=textContent

document.getElementById("myspan").textContent="newtext";
this will select dom-node with id myspan and change it text content to new text

You can do document.querySelector("[Span]").textContent = "content_to_display";

Can't be used with HTML code insertion, something like:
var a = "get the file <a href='url'>the link</a>"
var b = "get the file <a href='url'>another link</a>"
var c = "get the file <a href='url'>last link</a>"
using
document.getElementById("myspan").textContent=a;
on
<span id="myspan">first text</span>
with a timer but it just shows the reference target as text not runing the code, even tho it does shows correctly on the source code. If the jquery approch is not really a solution, the use of:
document.getElementById("myspan").innerHTML = a to c;
is the best way to make it work.

const span = document.querySelector("#span");
const btn = document.querySelector("#changeBtn");
btn.addEventListener("click", () => {
span.innerText = "text changed"
})
<span id="span">Sample Text</span>
<button id="changeBtn">Change Text</button>

For this span
<span id="name">sdfsdf</span>
You can go like this :-
$("name").firstChild.nodeValue = "Hello" + "World";

(function ($) {
$(document).ready(function(){
$("#myspan").text("This is span");
});
}(jQuery));
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<span id="myspan"> hereismytext </span>
user text() to change span text.

I used this one document.querySelector('ElementClass').innerText = 'newtext';
Appears to work with span, texts within classes/buttons

For some reason, it seems that using "text" attribute is the way to go with most browsers.
It worked for me
$("#span_id").text("text value to assign");