Highlighting and formatting code snippets using JavaScript - javascript

I'm looking for a way to highlight and format code snippets passed as string for a live style guide. I'm playing around with highlighjs and prettify. They are really helpful and easy for highlighting, but I can't seem to figure out a way to format or whether they can actually do that or not.
By formatting, I mean tabs and newlines to make code legible. I need to pass code as a string to automate the output of dust template I'm using for the style guide.
That is, I want to pass:
"<table><tr><td class="title">Name</td><td class="title">Category</td><td class="title">Results</td></tr></table>"
And get something like:
<table>
<tr>
<td class="title">Name</td>
<td class="title">Category</td>
<td class="title">Results</td>
</tr>
</table>
Any ideas on how to accomplish this?
Thanks!

You could parse this as HTML into a DOM and than traverse every element writing it out and indenting it with every iteration.
This code will do the job. Feel free to use it and surely to improve it. It's version 0.0.0.1.
var htmlString = '<table><tr><td class="title">Name</td><td class="title">Category</td><td class="title">Results</td></tr></table>';
//create a containing element to parse the DOM.
var documentDOM = document.createElement("div");
//append the html to the DOM element.
documentDOM.insertAdjacentHTML('afterbegin', htmlString);
//create a special HTML element, this shows html as normal text.
var documentDOMConsole = document.createElement("xmp");
documentDOMConsole.style.display = "block";
//append the code display block.
document.body.appendChild(documentDOMConsole);
function indentor(multiplier)
{
//indentor handles the indenting. The multiplier adds \t (tab) to the string per multiplication.
var indentor = "";
for (var i = 0; i < multiplier; ++i)
{
indentor += "\t";
}
return indentor;
}
function recursiveWalker(element, indent)
{
//recursiveWalker walks through the called DOM recursively.
var elementLength = element.children.length; //get the length of the children in the parent element.
//iterate over all children.
for (var i = 0; i < elementLength; ++i)
{
var indenting = indentor(indent); //set indenting for this iteration. Starts with 1.
var elements = element.children[i].outerHTML.match(/<[^>]*>/g); //retrieve the various tags in the outerHTML.
var elementTag = elements[0]; //this will be opening tag of this element including all attributes.
var elementEndTag = elements[elements.length-1]; //get the last tag.
//write the opening tag with proper indenting to the console. end with new line \n
documentDOMConsole.innerHTML += indenting + elementTag + "\n";
//get the innerText of the top element, not the childs using the function getElementText
var elementText = getElementText(element.children[i]);
//if the texts length is greater than 0 put the text on the page, else skip.
if (elementText.length > 0)
{
//indent the text one more tab, end with new line.
documentDOMConsole.innerHTML += (indenting + indentor(1) ) + elementText+ "\n";
}
if (element.children[i].children.length > 0)
{
//when the element has children call function recursiveWalker.
recursiveWalker(element.children[i], (indent+1));
}
//if the start tag matches the end tag, write the end tag to the console.
if ("<"+element.children[i].nodeName.toLowerCase()+">" == elementEndTag.replace(/\//, ""))
{
documentDOMConsole.innerHTML += indenting + elementEndTag + "\n";
}
}
}
function getElementText(el)
{
child = el.firstChild,
texts = [];
while (child) {
if (child.nodeType == 3) {
texts.push(child.data);
}
child = child.nextSibling;
}
return texts.join("");
}
recursiveWalker(documentDOM, 1);
http://jsfiddle.net/f2L82m8h/

Related

Can I get one symbol from string after clicking?

I have DOM document with text content like as:
<p>Content scripts aren't completely cut off from their parent extensions. A content script can exchange messages with its parent extension</p>
When I click over this HTML(text) I get nodeValue as text. But can I get only symbol from text over was click?
For example, I do click over symbol s in text:
<p>They support then</p>
So this is a fairly simple pattern when one wants to do operations on single characters, but you have data in blocks of paragraph or word. The first thing to do would be to iterate through all paragraphs, like so:
var paras = document.querySelectorAll('p');
for (var i = 0; i < paras.length; i++) {
var para = paras[i];
var text = para.textContent;
var split = para.split('');
var newText = '';
for (var j = 0; j < split.length; j++) {
newText += '<span class="char">' + split[j] + '</span>';
}
para.innerHTML = newText;
}
Then, you would want to set up a click listener on the body or on each paragraph, and the event (having been produced from clicking one of the single-character spans) would contain all the position information of that specific character.
document.body.addEventListener('click', function(e) {
if (e.target.classList.contains('char')) {
console.log(e.clientLeft, e.clientTop);
}
});
A possible advantage of this method over Selection.focusNode is that it also allows the single character to be modified as an element, not just ascertained.
Note that this will destroy events and object references -- if you need to persist those, use something like jQuery's replaceWith and iterate over the text nodes.

JavaScript get textContent excluding children

First, I'm creating a library for JavaScript and I can not use jQuery. I'm trying to get the text content of an HTML element without the text contents of its children.
Both attributes innerText and textContent don't give me what needed, please help.
You can solve using DOM API as childNodes and nodeType.
var elChildNode = document.querySelector("#hello").childNodes;
var sChildTextSum = "";
elChildNode.forEach(function(value){
if(value.nodeType === Node.TEXT_NODE) {
console.log("Current textNode value is : ", value.nodeValue.trim());
sChildTextSum += value.nodeValue;
}
});
console.log("All text value of firstChild : ", sChildTextSum);
I created a sample code as above.
https://jsfiddle.net/nigayo/p7t9bdc3/
To get Author's Name from the following element, excluding <span>...:
<div class="details__instructor">
Author's Name<span ng-show="job_title">, Entrepreneur</span>
</div>
use childNodes[0]. For example:
document.querySelector('div.details__instructor').childNodes[0].textContent
Using only JavaScript (you specified you cannot use jQuery), and given that you have provided and know the id for the parent element:
document.getElementById('parent_element_id').childNodes[0].nodeValue;
You can also use .trim() to remove any trailing space characters left behind from the removal of any child element text:
document.getElementById('parent_element_id').childNodes[0].nodeValue.trim();
var mydiv = getElementByID("id");
function Get_text(element) {
var selected = element.cloneNode(true);
var text;
while (selected.firstChild) {
if (selected.firstChild.nodeType == 3) text = selected.firstChild.nodeValue;
selected.removeChild(selected.firstChild);
}
return text;
}
Get_text(mydiv);
I know many good solutions here exist, but none of them actually achieved what I needed (get the textContent of a single node, none of its children), so sharing this for future searchers.
var html = document.getElementsByTagName("*");
for (var i = 0; i < html.length; i++) {
var el = html[i];
for (var j = 0; j < el.children.length; j++) {
var child = el.children[j],
childTextContent = child.innerHTML;
// Remove all children tags, leaving only the actual text of the node.
childTextContent = childTextContent.replace(/\<.*\>.*\<\/.*\>/gmi, "");
// Also remove <img /> type tags.
childTextContent = childTextContent.replace(/\<.*\ \/\>/gmi, "");
console.log(childTextContent);
// Now you can do any type of text matching (regex) on the result.
}
});

Add spans to characters in a string (in an HTML element)

I want to loop through the characters of a text in an element and add spans to the characters. This is pretty easy using jQuery.map():
$elem = $('h1');
var chars = jQuery.map($elem.text().split(''), function(c) {
return '<span>' + c + '</span>';
});
$elem.html(chars.join(''));
The above works great with a simple string, but now I want to change the function so that it also will handle more 'complex' contents like: <h1>T<em>e</em><b>st</b></h1>. Which should be translated to: <h1><span>T</span><em><span>e</span></em><b><span>s</span><span>t</span></b></h1>.
This means I cannot simply loop through all the characters in the element anymore. Is there something I can use to loop through the contents (characters) of an element as well as all children? Or is there another way of achieveing what I want?
Overall idea:
You can recursively iterate over the child nodes. If you encounter an element node, you iterate over its children etc. If you encounter a text node, you are replacing it with a series of span elements.
jQuery
function wrapCharacters(element) {
$(element).contents().each(function() {
if(this.nodeType === 1) {
wrapCharacters(this);
}
else if(this.nodeType === 3) {
$(this).replaceWith($.map(this.nodeValue.split(''), function(c) {
return '<span>' + c + '</span>';
}).join(''));
}
});
}
wrapCharacters($('h1')[0]);
DEMO
JavaScript (without jQuery)
The idea stays the same, and even without jQuery, wrapping each character is not very difficult:
var d_ = document.createDocumentFragment();
for(var i = 0, len = this.nodeValue.length; i < len; i++) {
var span = document.createElement('span');
span.innerHTML = this.nodeValue.charAt(i);
d_.appendChild(span);
}
// document fragments are awesome :)
this.parentNode.replaceChild(d_, this);
Only iterating over the child nodes has to be done carefully because text nodes are getting removed during iteration.
Plain JavaScript example
Try something like (untested):
function recursivelyWrapTextNodes($node) {
$node.contents().each(function() {
var $this = $(this);
if (this.nodeType === 3) { //Node.TEXT_NODE (IE...)
var spans = $.each($this.text().split(""), function(index, element) {
var $span = $("<span></span>");
$span.text(element);
$span.insertBefore($this);
});
$this.remove();
}
else if (this.nodeType === 1) //Node.ELEMENT_NODE
recursivelyWrapTextNodes($this);
}
Example: http://jsfiddle.net/Ymcha/
This is a pure javascript solution
/**
* Enclose every character of a string into a span
* #param text Text whose characters will be spanned
* #returns {string} The "spanned" string
*/
function spanText(text) {
return "<span class='char'>" +
text.split("").join("<\/span><span class='char'>") + "<\/span>";
}
var text = "Every character will be in a span";
document.getElementById("testContent").innerHTML = spanText(text);
document.getElementById("showSpans").textContent = spanText(text);
.char{background-color: grey;}
<! --- Demo for spanning all characters -->
<h3> Spanned text is highlighted grey </h3>
<p id="testContent"> Spanned material here</p>
<h3> This is how the above Highlighted text looks </h3>
<p id="showSpans"></p>

how to dynamically address a word/string with javascript in an html-document and then tag it?

I have an HTML-document:
<html>
<body>
<p>
A funny joke:
<ul>
<li>do you know why six is afraid of seven?
<li>because seven ate nine.
</ul>
Oh, so funny!
</p>
</body>
</html>
Now I want to identify the first occurence of "seven" and tag it with
<span id="link1" class="link">
How can this be accomplished?
Do you have to parse the DOM-tree or is it possible to get the whole code within the body-section and then search for the word?
In both cases, after I found the word somewhere, how do you identify it and change it's DOM-parent to span (I guess that's what has to be done) and then add the mentioned attributes?
It's not so much a code I would expect, but what methods or concepts will do the job.
And I am not so much intersted in a framework-solution but in a pure javascript way.
You need to find a DOM node with type TEXT_NODE (3) and containig your expected word. When you need to split a that node into three ones.
First is a TEXT_NODE which contains a text before the word you search, second one is a SPAN node containing the word you search, and third one is another TEXT_NODE containing an original node's tail (all after searched word).
Here is a source code...
<html>
<head>
<style type="text/css">
.link {
color: red;
}
</style>
</head>
<body>
<p>
A funny joke:
<ul>
<li>do you know why six is afraid of seven?
<li>because seven ate nine.
</ul>
Oh, so funny!
</p>
<script type="text/javascript">
function search(where, what) {
var children = where.childNodes;
for(var i = 0, l = children.length; i < l; i++) {
var child = children[i], pos;
if(child.nodeType == 3 && (pos = child.nodeValue.indexOf(what)) != -1) { // a TEXT_NODE
var value = child.nodeValue;
var parent = child.parentNode;
var start = value.substring(0, pos);
var end = value.substring(pos + what.length);
var span = document.createElement('span');
child.nodeValue = start;
span.className = 'link';
span.id = 'link1';
span.innerHTML = what;
parent.appendChild(span);
parent.appendChild(document.createTextNode(end));
return true;
} else
if(search(child, what))
break;
}
return false;
}
search(document.getElementsByTagName('body')[0], 'seven');
</script>
</body>
</html>
This is a function I’ve written a few years ago that searches for specific text, and highlights them (puts the hits in a span with a specific class name).
It walks the DOM tree, examining the text content. Whenever it finds a text node containing the looked-for text, it will replace that text node by three new nodes:
one text node with the text preceding the match,
one (newly created) span element containing the matching text,
and one text node with the text following the match.
This is the function as I have it. It’s part of a larger script file, but it should run independently as well. (I’ve commented out a call to ensureElementVisible which made the element visible, since the script also had folding and expanding capabilities).
It does one (other) thing that you probably won’t need: it turns the search text into a regular expression matching any of the multiple words.
function findText(a_text, a_top) {
// Go through *all* elements below a_top (if a_top is undefined, then use the body)
// and check the textContent or innerText (only if it has textual content!)
var rexPhrase = new RegExp(a_text.replace(/([\\\/\*\?\+\.\[\]\{\}\(\)\|\^\$])/g, '\\$1').replace(/\W+/g, '\\W*')
, 'gi');
var terms = [];
var rexSearchTokens = /[\w]+/g;
var match;
while(match = rexSearchTokens.exec(a_text)) {
terms.push(match[0]);
}
var rexTerm = new RegExp('\\b(' + terms.join('|') + ')', 'gi');
var hits = [];
walkDOMTree(a_top || document.body,
function search(a_element) {
if (a_element.nodeName === '#text') {
if(rexPhrase.test(a_element.nodeValue)) {
// ensureElementVisible(a_element, true);
hits.push(a_element);
}
}
});
// highlight the search terms in the found elements
for(var i = 0; i < hits.length; i++) {
var hit = hits[i];
var parent = hit.parentNode;
if (parent.childNodes.length === 1) {
// Remove the element from the hit list
hits.splice(i, 1);
var text = hit.nodeValue;
parent.removeChild(hit);
var match, prevLastIndex = 0;
while(match = rexTerm.exec(text)) {
parent.appendChild(document.createTextNode(text.substr(prevLastIndex, match.index - prevLastIndex)));
var highlightedTerm = parent.appendChild(document.createElement('SPAN'));
highlightedTerm.className = 'search-hit';
highlightedTerm.appendChild(document.createTextNode(match[0]));
prevLastIndex = match.index + match[0].length;
// Insert the newly added element into the hit list
hits.splice(i, 0, highlightedTerm);
i++;
}
parent.appendChild(document.createTextNode(text.substr(prevLastIndex)));
// Account for the removal of the original hit node
i--;
}
}
return hits;
}
I found the following so question:
Find text string using jQuery?
This appears to be close to what you're trying to do. Now are you attempting to wrap just the text "seven" or are you attempting to wrap the entire content of the <li>?

JavaScript to add HTML tags around content

I was wondering if it is possible to use JavaScript to add a <div> tag around a word in an HTML page.
I have a JS search that searches a set of HTML files and returns a list of files that contain the keyword. I'd like to be able to dynamically add a <div class="highlight"> around the keyword so it stands out.
If an alternate search is performed, the original <div>'s will need to be removed and new ones added. Does anyone know if this is even possible?
Any tips or suggestions would be really appreciated.
Cheers,
Laurie.
In general you will need to parse the html code in order to ensure that you are only highlighting keywords and not invisible text or code (such as alt text attributes for images or actual markup). If you do as Jesse Hallett suggested:
$('body').html($('body').html().replace(/(pretzel)/gi, '<b>$1</b>'));
You will run into problems with certain keywords and documents. For example:
<html>
<head><title>A history of tables and tableware</title></head>
<body>
<p>The table has a fantastic history. Consider the following:</p>
<table><tr><td>Year</td><td>Number of tables made</td></tr>
<tr><td>1999</td><td>12</td></tr>
<tr><td>2009</td><td>14</td></tr>
</table>
<img src="/images/a_grand_table.jpg" alt="A grand table from designer John Tableius">
</body>
</html>
This relatively simple document might be found by searching for the word "table", but if you just replace text with wrapped text you could end up with this:
<<span class="highlight">table</span>><tr><td>Year</td><td>Number of <span class="highlight">table</span>s made</td></tr>
and this:
<img src="/images/a_grand_<span class="highlight">table</span>.jpg" alt="A grand <span class="highlight">table</span> from designer John <span class="highlight">Table</span>ius">
This means you need parsed HTML. And parsing HTML is tricky. But if you can assume a certain quality control over the html documents (i.e. no open-angle-brackets without closing angle brackets, etc) then you should be able to scan the text looking for non-tag, non-attribute data that can be further-marked-up.
Here is some Javascript which can do that:
function highlight(word, text) {
var result = '';
//char currentChar;
var csc; // current search char
var wordPos = 0;
var textPos = 0;
var partialMatch = ''; // container for partial match
var inTag = false;
// iterate over the characters in the array
// if we find an HTML element, ignore the element and its attributes.
// otherwise try to match the characters to the characters in the word
// if we find a match append the highlight text, then the word, then the close-highlight
// otherwise, just append whatever we find.
for (textPos = 0; textPos < text.length; textPos++) {
csc = text.charAt(textPos);
if (csc == '<') {
inTag = true;
result += partialMatch;
partialMatch = '';
wordPos = 0;
}
if (inTag) {
result += csc ;
} else {
var currentChar = word.charAt(wordPos);
if (csc == currentChar && textPos + (word.length - wordPos) <= text.length) {
// we are matching the current word
partialMatch += csc;
wordPos++;
if (wordPos == word.length) {
// we've matched the whole word
result += '<span class="highlight">';
result += partialMatch;
result += '</span>';
wordPos = 0;
partialMatch = '';
}
} else if (wordPos > 0) {
// we thought we had a match, but we don't, so append the partial match and move on
result += partialMatch;
result += csc;
partialMatch = '';
wordPos = 0;
} else {
result += csc;
}
}
if (inTag && csc == '>') {
inTag = false;
}
}
return result;
}
Wrapping is pretty easy with jQuery:
$('span').wrap('<div class="highlight"></div>'); // wraps spans in a b tag
Then, to remove, something like this:
$('div.highlight').each(function(){ $(this).after( $(this).text() ); }).remove();
Sounds like you will have to do some string splitting, though, so wrap may not work unless you want to pre-wrap all your words with some tag (ie. span).
The DOM API does not provide a super easy way to do this. As far as I know the best solution is to read text into JavaScript, use replace to make the changes that you want, and write the entire content back. You can do this either one HTML node at a time, or modify the whole <body> at once.
Here is how that might work in jQuery:
$('body').html($('body').html().replace(/(pretzel)/gi, '<b>$1</b>'));
couldn't you just write a selector as such to wrap it all?
$("* :contains('foo')").wrap("<div class='bar'></div>");
adam wrote the code above to do the removal:
$('div.bar').each(function(){ $(this).after( $(this).text() ); }).remove();
edit: on second thought, the first statement returns an element which would wrap the element with the div tag and not the sole word. maybe a regex replace would be a better solution here.

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