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How do I copy an HTML document and edit the copy based upon the selection, without altering the original document?

I have an HTML document, and I would like to remove some of the tags from it dynamically using Javascript, based on whether the tags are within the current selection or not. However, I do not want to update the actual document on the page, I want to make a copy of the whole page's HTML and edit that copy. The problem is that the Range object I get from selection.getRangeAt(0) still points to the original document, as far as I can see.
I've managed to get editing the original document in place with this code:
var node = window.getSelection().getRangeAt(0).commonAncestorContainer;
var allWithinRangeOfParent = node.getElementsByTagName("*");
for (var i=0, el; el = allWithinRangeParent[i]; i++) {
// The second parameter says to include the element
// even if it's not fully selected
if (selection.containsNode(el, true) ) {
el.remove();
}
}
But what I want to do is to somehow perform the same operation with removing elements, but remove them from a copy of the original HTML. I've made the copy like this: var fullDocument = $('html').clone(); How could I accomplish this?

Either dynamically add a class or data attribute to all your elements on load before you clone so that you have a point of reference then grab the class or data attribute on the common ancestor and remove it from the clone. I can give an example if you like? Along these lines - http://jsfiddle.net/9s9hpc2v/ isn't properly working exactly right but you get the gist.
$('*').each(function(i){
$(this).attr('data-uniqueId', i);
});
var theclone = $('#foo').clone();
function laa(){
var node = window.getSelection().getRangeAt(0).commonAncestorContainer;
if(node.getElementsByTagName){
var allWithinRangeOfParent = $(node).find('*');
console.log(allWithinRangeOfParent, $(allWithinRangeOfParent).attr('data-uniqueId'));
$.each(allWithinRangeOfParent, function(){
theclone.find('[data-uniqueId="'+$(this).attr('data-uniqueId')+'"]').remove();
});
console.log(theclone.html());
}
}
$('button').click(laa);

How child elements associated with input search text can also be listed, using TreeListFilter?

Using TreeListFilter.js from http://wiki.aiwsolutions.net/2014/03/12/tree-list-filter-plugin/
I tried to modify the code to make child elements (ul/li) of a matched input search text be listed as well, but it is not working. Still, display stops at the matching level in the unordered list.
Would appreciate any help.

I think the key change you need to make is to search the current node's immediate text only first, then ensure this result is communicated to child nodes.
// Search own text only (not including children)
var text = liObject.clone().children().remove().end().text();
// Match or parent is visible
display = text.toLowerCase().indexOf(filterValue) >= 0 || parentDisplay;
if (liObject.children().length > 0) {
for (var j = 0; j < liObject.children().length; j++) {
// Ask child to search self and let them know parents display result
var subDisplay = filterList(jQuery(liObject.children()[j]), filterValue, display);
// If child is visible at this stage, make parent visible, if
// parent visible, this will already be true
display = display || subDisplay;
}
}
Full example is here: https://jsfiddle.net/on2u2584/1/

Performant append to array of existing DOM elements

I have the following piece of code, that loops over an Array of DOM objects, runs a test and appends some text to the node if returns true.
$.each( selections, function ( i, e ) {
var test = some_test(e);
if(test) {
$(e).append('passed');
}
});
Whilst this code works fine, on a large set it is obviously going to perform a lot of appends to the DOM. This article on reasons to use append correctly demonstrates how appending to the DOM is far more performant :
var arr = reallyLongArray;
var textToInsert = [];
var i = 0;
$.each(arr, function(count, item) {
textToInsert[i++] = '<tr><td name="pieTD">';
textToInsert[i++] = item;
textToInsert[i++] = '</td></tr>';
});
$('table').append(textToInsert.join(''));
My question is what is the most performant way to make changes to a set of existing DOM elements without having to call .append on each element ? The above example demonstrates the creation of a new element. Is this the only way ?

What makes live DOM manipulations slow is mainly the fact that it's causing DOM reflows for most manipulations that are made. Therefore, you should strive to reduce the amount of DOM reflows by reducing the number of live DOM manipulations.
If you want to manipulate multiple elements that are already part of the DOM, one strategy that can be used is to temporarly remove the parent of those nodes from the DOM, manipulate the elements and then re-attach the parent node where it was.
In the exemple below, I detach the table before manipulating it's rows and then reattach it to the DOM. That's 2 reflows rather than n reflows.
var data = [1, 2, 3, 4, 5, 6, 7];
populateCells(document.querySelector('table'), data);
function populateCells(table, data) {
var rows = table.rows,
reAttachTable = temporarilyDetachEl(table);
data.forEach(function (num, i) {
rows[i].cells[0].innerHTML = num;
});
reAttachTable();
}
function temporarilyDetachEl(el) {
var parent = el.parentNode,
nextSibling = el.nextSibling;
parent.removeChild(el);
return function () {
if (nextSibling) parent.insertBefore(el, nextSibling);
else parent.appendChild(el);
};
}
<table>
<tr><td></td></tr>
<tr><td></td></tr>
<tr><td></td></tr>
<tr><td></td></tr>
<tr><td></td></tr>
<tr><td></td></tr>
<tr><td></td></tr>
</table>

You could completely rebuild the set of DOM elements using one of the techniques from the linked article, then clear the existing set and .append() the new one. But given that you already have the set and just want to adjust a subset of its items, there's nothing wrong with your existing code.

When talking about performance it is a good idea to profile your code so that you don't have to guess.
Here is a simple test case around this example:
http://jsperf.com/most-performant-way-to-append-to-dom-elements
(and related fiddle to demo the visual side of this: http://jsfiddle.net/f62ptjbf/)
This test compares four possible methods for doing this: (does not by any means cover all solutions)
Append "passed" as text node (like your example code)
Append "passed" as a SPAN node (slight variation to your example)
Build a DOM fragment that renders the nodes and records the "passed", then add to DOM as a single append operation from HTML string
Remove selection elements from DOM, manipulate them, then re-add to DOM.
It shows that [at least in my copy of Chrome browser] the fastest method is removal of elements before processing, then re-add to DOM after processing. (#4)
Here is another test that shows [at least in my copy of Chrome] it is faster to append SPAN elements with the text "passed" than it is to append text nodes.
http://jsperf.com/append-variations
Based on these findings, I could recommend two potential performance improvements to your code:
Remove DOM elements in selection before manipulating them, then re-add when finished.
Append a SPAN with the text "passed" instead of appending the text directly.
However, #1 works best if the elements have a shared parent. The performance will be a function of the number of append operations.

How to limit Javascript's window.find to a particular DIV?

Is it possible to use Javascript in Safari/Firefox/Chrome to search a particular div container for a given text string. I know you can use window.find(str) to search the entire page but is it possible to limit the search area to the div only?
Thanks!

Once you look up your div (which you might do via document.getElementById or any of the other DOM functions, various specs here), you can use either textContent or innerText to find the text of that div. Then you can use indexOf to find the string in that.
Alternately, at a lower level, you can use a recursive function to search through all text nodes in the window, which sounds a lot more complicated than it is. Basically, starting from your target div (which is an Element), you can loop through its childNodes and search their nodeValue string (if they're Texts) or recurse into them (if they're Elements).
The trick is that a naive version would fail to find "foo" in this markup:
<p><span>fo</span>o</p>
...since neither of the two Text nodes there has a nodeValue with "foo" in it (one of them has "fo", the other "o").

Depending on what you are trying to do, there is an interesting way of doing this that does work (does require some work).
First, searching starts at the location where the user last clicked. So to get to the correct context, you can force a click on the div. This will place the internal pointer at the beginning of the div.
Then, you can use window.find as usual to find the element. It will highlight and move toward the next item found. You could create your own dialog and handle the true or false returned by find, as well as check the position. So for example, you could save the current scroll position, and if the next returned result is outside of the div, you restore the scroll. Also, if it returns false, then you can say there were no results found.
You could also show the default search box. In that case, you would be able to specify the starting position, but not the ending position because you lose control.
Some example code to help you get started. I could also try putting up a jsfiddle if there is enough interest.
Syntax:
window.find(aStringToFind, bCaseSensitive, bBackwards, bWrapAround, bWholeWord, bSearchInFrames, bShowDialog);
For example, to start searching inside of myDiv, try
document.getElementById("myDiv").click(); //Place cursor at the beginning
window.find("t", 0, 0, 0, 0, 0, 0); //Go to the next location, no wrap around
You could set a blur (lose focus) event handler to let you know when you leave the div so you can stop the search.
To save the current scroll position, use document.body.scrollTop. You can then set it back if it trys to jump outside of the div.
Hope this helps!
~techdude

As per the other answer you won't be able to use the window.find functionality for this. The good news is, you won't have to program this entirely yourself, as there nowadays is a library called rangy which helps a lot with this. So, as the code itself is a bit too much to copy paste into this answer I will just refer to a code example of the rangy library that can be found here. Looking in the code you will find
searchScopeRange.selectNodeContents(document.body);
which you can replace with
searchScopeRange.selectNodeContents(document.getElementById("content"));
To search only specifically in the content div.

If you are still looking for someting I think I found a pretty nice solution;
Here it is : https://www.aspforums.net/Threads/211834/How-to-search-text-on-web-page-similar-to-CTRL-F-using-jQuery/
And I'm working on removing jQuery (wip) : codepen.io/eloiletagant/pen/MBgOPB
Hope it's not too late :)

You can make use of Window.find() to search for all occurrences in a page and Node.contains() to filter out unsuitable search results.
Here is an example of how to find and highlight all occurrences of a string in a particular element:
var searchText = "something"
var container = document.getElementById("specificContainer");
// selection object
var sel = window.getSelection()
sel.collapse(document.body, 0)
// array to store ranges found
var ranges = []
// find all occurrences in a page
while (window.find(searchText)) {
// filter out search results outside of a specific element
if (container.contains(sel.anchorNode)){
ranges.push(sel.getRangeAt(sel.rangeCount - 1))
}
}
// remove selection
sel.collapseToEnd()
// Handle ranges outside of the while loop above.
// Otherwise Safari freezes for some reason (Chrome doesn't).
if (ranges.length == 0){
alert("No results for '" + searchText + "'")
} else {
for (var i = 0; i < ranges.length; i++){
var range = ranges[i]
if (range.startContainer == range.endContainer){
// Range includes just one node
highlight(i, range)
} else {
// More complex case: range includes multiple nodes
// Get all the text nodes in the range
var textNodes = getTextNodesInRange(
range.commonAncestorContainer,
range.startContainer,
range.endContainer)
var startOffset = range.startOffset
var endOffset = range.endOffset
for (var j = 0; j < textNodes.length; j++){
var node = textNodes[j]
range.setStart(node, j==0? startOffset : 0)
range.setEnd(node, j==textNodes.length-1?
endOffset : node.nodeValue.length)
highlight(i, range)
}
}
}
}
function highlight(index, range){
var newNode = document.createElement("span")
// TODO: define CSS class "highlight"
// or use <code>newNode.style.backgroundColor = "yellow"</code> instead
newNode.className = "highlight"
range.surroundContents(newNode)
// scroll to the first match found
if (index == 0){
newNode.scrollIntoView()
}
}
function getTextNodesInRange(rootNode, firstNode, lastNode){
var nodes = []
var startNode = null, endNode = lastNode
var walker = document.createTreeWalker(
rootNode,
// search for text nodes
NodeFilter.SHOW_TEXT,
// Logic to determine whether to accept, reject or skip node.
// In this case, only accept nodes that are between
// <code>firstNode</code> and <code>lastNode</code>
{
acceptNode: function(node) {
if (!startNode) {
if (firstNode == node){
startNode = node
return NodeFilter.FILTER_ACCEPT
}
return NodeFilter.FILTER_REJECT
}
if (endNode) {
if (lastNode == node){
endNode = null
}
return NodeFilter.FILTER_ACCEPT
}
return NodeFilter.FILTER_REJECT
}
},
false
)
while(walker.nextNode()){
nodes.push(walker.currentNode);
}
return nodes;
}
For the Range object, see https://developer.mozilla.org/en-US/docs/Web/API/Range.
For the TreeWalker object, see https://developer.mozilla.org/en-US/docs/Web/API/TreeWalker

var elements = [];
$(document).find("*").filter(function () {
if($(this).text().contains(yourText))
elements.push($(this));
});
console.log(elements);
I didn't try it, but according the jQuery documentation it should work.

Here is how I am doing with jquery:
var result = $('#elementid').text().indexOf('yourtext') > -1
it will return true or false

Maybe you are trying to not use jquery...but if not, you can use this $('div:contains(whatyouarelookingfor)') the only gotcha is that it could return parent elements that also contain the child div that matches.

Calculating text selection offsets in nest elements in Javascript

The Problem
I am trying to figure out the offset of a selection from a particular node with javascript.
Say I have the following HTML
<p>Hi there. This <strong>is blowing my mind</strong> with difficulty.</p>
If I select from blowing to difficulty, it gives me the offset from the #text node inside of the <strong>. I need the string offset from the <p>'s innerHTML and the length of the selection. In this case, the offset would be 26 and the length would be 40.
My first thought was to do something with string offsets, etc. but you could easily have something like
<p> Hi there. This <strong>is awesome</strong>. For real. It <strong>is awesome</strong>.</p>
which would break that method because there are identical nodes. I also need the option to throw out nodes. Say I have something like this
<p>Hi there. This <strong>is blowing my mind</strong> with difficulty.</p>
I want to throw out an elements with rel="inserted" when I do the calculation. I still want 26 and 40 as the result.
What I'm looking for
The solution needs to be recursive. If there was a <span> with a <strong> in it, it would still need to traverse to the <p>.
The solution needs to remove the length of any element with rel="inserted". The contents are important, but the tags themselves are not. All other tags are important. I'd strongly prefer not to remove any elements from the DOM when I do all of this.
I am using document.getSelection() to get the selection object. This solution only has to work in WebKit. jQuery is an option, but I'd prefer to it without it if possible.
Any ideas would be greatly appreciated.
I have no control over the HTML I doing all of this on.

I think I solved my issue. I ended not calculating the offset like I originally planned. I am storing the "path" from the chunk (aka <p>). Here is the code:
function isChunk(node) {
if (node == undefined || node == null) {
return false;
}
return node.nodeName == "P";
}
function pathToChunk(node) {
var components = new Array();
// While the last component isn't a chunk
var found = false;
while (found == false) {
var childNodes = node.parentNode.childNodes;
var children = new Array(childNodes.length);
for (var i = 0; i < childNodes.length; i++) {
children[i] = childNodes[i];
}
components.unshift(children.indexOf(node));
if (isChunk(node.parentNode) == true) {
found = true
} else {
node = node.parentNode;
}
}
return components.join("/");
}
function nodeAtPathFromChunk(chunk, path) {
var components = path.split("/");
var node = chunk;
for (i in components) {
var component = components[i];
node = node.childNodes[component];
}
return node;
}
With all of that, you can do something like this:
var p = document.getElementsByTagName('p')[0];
var piece = nodeAtPathFromChunk(p, "1/0"); // returns desired node
var path = pathToChunk(piece); // returns "1/0"
Now I just need to expand all of that to support the beginning and the end of a selection. This is a great building block though.

What does this offset actually mean? An offset within the innerHTML of an element is going to be extremely fragile: any insertion of a new node or change to an attribute of an element preceding the point in the document the offset represents is going to make that offset invalid.
I strongly recommend using the browser's built-in support for this in the form of DOM Range. You can get hold of a range representing the current selection as follows:
var range = window.getSelection().getRangeAt(0);
If you're going to be manipulating the DOM based on this offset that you want, you're best off doing so using nodes instead of string representations of those nodes.

you can use the following java script code:
var text = window.getSelection();
var start = text.anchorOffset;
alert(start);
var end = text.focusOffset - text.anchorOffset;
alert(end);

Just check if your selected element is a paragraph, and if not use something like Prototype's Element.up() method to select the first paragraph parent.
For example:
if(selected_element.nodeName != 'P') {
parent_paragraph = $(selected_element).up('p');
}
Then just find the difference between the parent_paragraph's text offset and your selected_element's text offset.

Maybe you could use the jQuery selectors to ignore the rel="inserted"?
$('a[rel!=inserted]').doSomething();
http://api.jquery.com/attribute-not-equal-selector/
What code are you using now to select from blowing to difficulty?