I'm trying to make a JavaScript bookmarklet that will act as a highlighter, changing the background of selected text on a webpage to yellow when the bookmarklet is pressed.
I'm using the following code to get the selected text, and it works fine, returning the correct string
function getSelText() {
var SelText = '';
if (window.getSelection) {
SelText = window.getSelection();
} else if (document.getSelection) {
SelText = document.getSelection();
} else if (document.selection) {
SelText = document.selection.createRange().text;
}
return SelText;
}
However, when I created a similar function to change the CSS of the selected text using jQuery, it isn't working:
function highlightSelText() {
var SelText;
if (window.getSelection) {
SelText = window.getSelection();
} else if (document.getSelection) {
SelText = document.getSelection();
} else if (document.selection) {
SelText = document.selection.createRange().text;
}
$(SelText).css({'background-color' : 'yellow', 'font-weight' : 'bolder'});
}
Any ideas?
The easiest way to do this is to use execCommand(), which has a command to change the background colour in all modern browsers.
The following should do what you want on any selection, including ones spanning multiple elements. In non-IE browsers it turns on designMode, applies a background colour and then switches designMode off again.
UPDATE
Fixed in IE 9.
function makeEditableAndHighlight(colour) {
var range, sel = window.getSelection();
if (sel.rangeCount && sel.getRangeAt) {
range = sel.getRangeAt(0);
}
document.designMode = "on";
if (range) {
sel.removeAllRanges();
sel.addRange(range);
}
// Use HiliteColor since some browsers apply BackColor to the whole block
if (!document.execCommand("HiliteColor", false, colour)) {
document.execCommand("BackColor", false, colour);
}
document.designMode = "off";
}
function highlight(colour) {
var range, sel;
if (window.getSelection) {
// IE9 and non-IE
try {
if (!document.execCommand("BackColor", false, colour)) {
makeEditableAndHighlight(colour);
}
} catch (ex) {
makeEditableAndHighlight(colour)
}
} else if (document.selection && document.selection.createRange) {
// IE <= 8 case
range = document.selection.createRange();
range.execCommand("BackColor", false, colour);
}
}
Here is a crude example of how it could work. As Zack points out you'll need to be aware of cases where the selection spans multiple elements. This isn't intended to be used as-is, just something to help get ideas flowing. Tested in Chrome.
var selection = window.getSelection();
var text = selection.toString();
var parent = $(selection.focusNode.parentElement);
var oldHtml = parent.html();
var newHtml = oldHtml.replace(text, "<span class='highlight'>"+text+"</span>");
parent.html( newHtml );
To make the highlight stick permanently, I believe you are going to have to wrap the selection in a new DOM element (span should do), to which you can then attach style properties. I don't know if jQuery can do that for you. Keep in mind that selections can span element boundaries, so in the general case you're going to have to inject a whole bunch of new elements
Have a look at a little example i made at http://www.jsfiddle.net/hbwEE/3/
It does not take into account selections that span multiple elements..
(IE will do but will mess the html a bit ..)
In Firefox, you can use the ::-moz-selection psuedo-class.
In Webkit, you can use the ::selection pseudo-class.
I like Tim's answer, it's clean and fast. But it also shuts down the doors to doing any interactions with the highlights.
Inserting inline elements directly around the texts is a bad choice, as they broke the text flow and mess things up in complex situations,
So I suggest a dirty hack that
calculates the absolute layout of each line of selected text (no matter where they are),
then insert colored, semi-transparent inline-block elements in the end of the document body.
This chrome extension is an example of how this can be done.
It uses API from this library to get the absolute layout of each selected line.
Related
Is there any way to detect with JavaScript/jQuery if an element is strike-through and underlined.
So let's say we have:
<u><s>text here.</s>other text here.</u>
Is it possible to detect if the text within <s> is also underlined?
*Ideally, it would not be allowed to look if <u> has any <s> children.
I've been toying around with it and it seems peculiar that both styles use the same CSS property, which in turn makes me wonder how it even works in the first place.
To make my problem clearer:
I'm playing around with a self-made wysiwyg editor, for usability reasons I'm trying to implement a listener on the text which alters (lights up) editing buttons. e.g. when a part of text is bold the "B" button changes to an active state. I'm currently handling this by getting the element at the cursor and checking if the element is bold or inherits it.
The problem with underline and striketrough is that they are neither overwriting the text-decoration attribute of each other, and are not visible in css
when I put the cursor on a underlined text-fragment, the text-decoration property only shows as underline, while the text is both underline and line-through. In such situations I cannot know what the exact relation is between the <u> element and the <s> element; the <s> element could be 100 parents back as far as I could know.
A lot of text, but I hope it kinda clears up my situation.
Here is the robust way of doing it. #Cheery answer works well but it fails if italic or underline or any other font-style provided through CSS. Credit is given to Tim Down for his numerous answers for these kind of questions.
function checkState(element, check) {
var doc = document;
var text = doc.getElementById(element);
if (doc.body.createTextRange) { // ms
var range = doc.body.createTextRange();
range.moveToElementText(text);
range.select();
} else if (window.getSelection) { // moz, opera, webkit
var selection = window.getSelection();
var range = doc.createRange();
range.selectNodeContents(text);
selection.removeAllRanges();
selection.addRange(range);
}
var range, checked = false;
if (window.getSelection) {
var sel = window.getSelection();
if (sel && sel.getRangeAt && sel.rangeCount) {
range = sel.getRangeAt(0);
document.designMode = "on";
sel.removeAllRanges();
sel.addRange(range);
}
}
if (document.queryCommandState) {
checked = document.queryCommandState(check);
}
if (document.designMode == "on") {
document.designMode = "off";
}
if (window.getSelection) {
if (window.getSelection().empty) { // Chrome
window.getSelection().empty();
} else if (window.getSelection().removeAllRanges) { // Firefox
window.getSelection().removeAllRanges();
}
} else if (document.selection) { // IE?
document.selection.empty();
}
return checked;
}
alert(checkState('c', 'underline')); // italic, bold etc..
var str = '<u><s>text here.</s>other text here.</u>';
var el = $('<div>').html(str);
alert($('u s', el).length);
what if the combination is or even something like
so what, check inverse too..
var str = '<s><div><u></u></div><p><u></u></p></s>';
var el = $('<div>').html(str);
alert($('u s', el).length || $('s u', el).length);
if the initial string is not a valid html then you do not know how some browsers will behave at its output.
ps: made some simple example, by click..
$(function(){
$('.wrapper').on('click', '*', function() {
var styles = ['line-through', 'underline'], counter = [0, 0], tags = ['S', 'U'];
$(this).parentsUntil('.wrapper').andSelf().each(function() {
var current = $(this).css('text-decoration'), $tag = $(this)[0];
$.each(styles, function(index, style) {
if (current.indexOf(style) > -1 || $tag.tagName == tags[index]) counter[index] += 1;
});
});
var results = [];
if (counter[0] > 0) results.push('striked');
if (counter[1] > 0) results.push('underlined');
alert(results.join(' and '));
return false;
});
});
.strike {
text-decoration: line-through;
}
.underline {
text-decoration: underline;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<div class='wrapper'>
<div class='strike'>
striked <u>underlined</u>
</div>
<div class='underline'>
underlined <s>striked</s>
</div>
</div>
A somewhat horrible approach, but the only way I could see that doesn't involve explicitly checking nesting, or relying on default CSS surviving any theming (<s> won't always, necessarily, have text-decoration: line-through;, similarly <u> won't always, necessarily, have text-decoration: underline;):
// the text-decoration styles you want to find:
var styles = ['line-through', 'underline'];
// finding all elements within the <body>, and
// filtering them:
var underlinedAndLineThrough = $('body *').filter(function() {
// caching because of re-use:
var self = $(this),
decor = self.css('text-decoration');
// if the 'text-decoration' style is found in the array of styles we're
// looking for:
if (styles.indexOf(decor) > -1) {
// we add that style as a class-name to the current element, and all
// descendants:
self.find('*').add(self).addClass(decor);
// we return the current element (to keep it in the collection):
return self;
}
// filtering again:
}).filter(function(){
// we keep the current element of the collection if it has all the css styles
// we're looking for:
return $(this).is('.' + styles.join('.'));
});
console.log(underlinedAndLineThrough);
JS Fiddle demo.
References:
JavaScript:
Array.prototype.indexOf().
Array.prototype.join().
jQuery:
add().
addClass().
filter().
find().
is().
I know how to set an <a /> tag with the href attribute in a contenteditable like this:
execCommand("CreateLink", false, "#jumpmark");
which will result in
selection
However I cannot figure out how to set an anchor name instead of the href.
This is my desired result:
<a name="jumpmark">selection</a>
Can anyone help me?
Side notes: I am using jQuery and Rangy as libraries, however I would prefer a solution that works directly with execCommand.
Update: Here's a jsfiddle: http://jsfiddle.net/fjYHr/ Select some text and click the button. All I want is that with the button click a link is inserted with a name attribute set instead of the href.
You could use something like the following, which is adapted from the pasteHtmlAtCaret() function from this answer of mine:
Demo: http://jsfiddle.net/F8Zny/
Code:
function surroundSelectedText(element) {
var sel, range;
if (window.getSelection) {
// IE9 and non-IE
sel = window.getSelection();
if (sel.getRangeAt && sel.rangeCount) {
range = sel.getRangeAt(0);
element.appendChild( document.createTextNode(range.toString()) );
range.deleteContents();
range.insertNode(element);
// Preserve the selection
range = range.cloneRange();
range.setStartAfter(element);
range.collapse(true);
sel.removeAllRanges();
sel.addRange(range);
}
} else if (document.selection && document.selection.type != "Control") {
// IE < 9
var selRange = document.selection.createRange();
element.appendChild( document.createTextNode(selRange.text) );
selRange.pasteHTML(element.outerHTML);
}
}
If you must use document.execCommand() then you could use the InsertHTML command in non-IE browsers. However, IE does not support it.
document.execCommand("InsertHTML", false, '<a name="jumpmark">selection</a>');
I see you're using Rangy, but I don't how to use it at all. Before I realized what Rangy was, I looked up how to get the current selection. I found a function that gets it and replaces it with a passed in value. I ended up modfiying it, but here it is:
http://jsfiddle.net/fjYHr/1/
$(document).ready(function () {
$("#setlink").click(function () {
replaceSelectedText("jumplink");
});
});
function replaceSelectedText(nameValue) {
var sel, sel2, range;
if (window.getSelection) {
sel = window.getSelection();
sel2 = ""+sel; // Copy selection value
if (sel.rangeCount) {
range = sel.getRangeAt(0);
range.deleteContents();
var newA = document.createElement("a");
newA.name = nameValue;
newA.innerHTML = sel2;
range.insertNode(newA);
}
} else if (document.selection && document.selection.createRange) {
// Not sure what to do here
range = document.selection.createRange();
var newA = "<a name='" + nameValue.replace(/'/g, "") + "'>" + range.text + "</a>";
range.text = newA;
}
}
Notice how I store the original current selection, then replace it with an <a> element that gets its name set with the passed-in value.
As for the document.selection part (which seems to be used by IE < 9), I'm not 100% sure that the code I provided will work (actually allow HTML in the selection, and not escaping it). But it's my attempt :)
As you've seen execCommand is rather limited in the attributes you can set, as such you cannot set the name attribute using it - only the href.
As you have jQuery set as a tag, you can use that as an alternative:
var $a = $('<a></a>').attr('name', 'jumpmark').appendTo('body');
Update
I need to work on the current selection. Specifically I don't have a jQuery object that I can append to, meaning I don't have a DOM node that I can work on
In this case use a plugin such as Rangy to get the selection which you can then amend with jQuery as required.
Here is my question:
When the user makes a selection in an article or in the editing area of a WYSWYG editor widget,
the selection can span over multiple elements,
like anchors, images, span tags... even block-level elements (but no table in my problem).
I know how to retrieve a Range object from the selection,
but could not find a reliable solution to get the content text of the Range object.
I'm not looking for a solution for IE (its TextRange object has a .text property).
Thanks!
Have you looked at the quirksmode article on Range?
Based on this article, you could create a method like this:
function getRangeText() {
var userSelection;
if (window.getSelection) {
userSelection = window.getSelection();
} else if (document.selection) {
userSelection = document.selection.createRange();
}
var selectedText = userSelection;
if (userSelection.text) {
selectedText = userSelection.text;
}
return selectedText;
}
I tested this in FF5, Opera 11, Safari on the Mac, as well as IE6 and IE7. It's worth testing in the other IE browsers, but my guess is it works in them, as well.
This returns a string and works in all major browsers:
function getSelectionText() {
var text = ""
if (window.getSelection) {
text = window.getSelection().toString();
} else if (document.selection && document.selection.type == "Text") {
text = document.selection.createRange().text;
}
return text;
}
Let's say I highlight some text on the page using my mouse. How can I remove all highlighted text using JavaScript?
Thank you.
I've understood the question a bit differently. I believe you want to know how to delete the selected text from the document, in which case you could use:
function deleteSelection() {
if (window.getSelection) {
// Mozilla
var selection = window.getSelection();
if (selection.rangeCount > 0) {
window.getSelection().deleteFromDocument();
window.getSelection().removeAllRanges();
}
} else if (document.selection) {
// Internet Explorer
var ranges = document.selection.createRangeCollection();
for (var i = 0; i < ranges.length; i++) {
ranges[i].text = "";
}
}
}
If you just want to clear the highlight itself, and not remove the text being highlighted, the following should do the trick:
function clearSelection() {
if (window.getSelection) {
window.getSelection().removeAllRanges();
} else if (document.selection) {
document.selection.empty();
}
}
IE 4 and old Netscape used to have a method to do just this... It's not longer proper (nor supported).
Your best guess would be to use Javascript to focus() on an object, and then blur() as well -- effectively like clicking away from the object.
document.getElementById("someObject").focus();
document.getElementById("someObject").blur();
I wanna modify the document selection (user currently selected by mouse or keyboard), how to do it in a cross browser way?
I have not worked with text selection enough to provide real help, but what you are trying to do can be done. You will want to look into the following two functions:
createRange() MSDN | MDC
getRangeAt() MDC
I know it can be implemented cross browser. You can see some of it in action here:
http://fuelyourcoding.com/a-few-strategies-for-using-javascript/
By scrolling to the bottom and clicking the Elephant Icon, which uses the Evernote script. However, my script first selects the main content area (you will see it flash orange) and then it deselects once the capture is made.
Here is a mini jQuery plugin that does it. It was adapted by me from some site, and like the comments say, I feel horrible for not remembering. Its really important to note I adapted it to jQuery, but the code came from some site where they explained how to do it:
// Adapted this from somewhere. Feel horrible for not remembering.
$.fn.autoSelect = function(){
var selectTarget = this[0]; // Select first element from jQuery collection
if(selectTarget != null) {
if(selectTarget.tagName == 'TEXTAREA' || (selectTarget.tagName == "INPUT" && selectTarget.type == "text")) {
selectTarget.select();
} else if(window.getSelection) { // FF, Safari, Opera
var sel = window.getSelection();
var range = document.createRange();
range.selectNode(selectTarget);
sel.removeAllRanges();
sel.addRange(range);
} else { // IE
document.selection.empty();
var range = document.body.createTextRange();
range.moveToElementText(selectTarget);
range.select();
};
};
return this; // Don't break the chain
};
It seems this script is a few places online, but here is another variation on it
As an example, and the easiest one, let's say you want to move the user's selection to contain the contents of an element. The following will work in all major browsers:
function selectElementContents(el) {
var body = document.body, range, sel;
if (body.createTextRange) {
range = body.createTextRange();
range.moveToElementText(el);
range.select();
} else if (document.createRange && window.getSelection) {
range = document.createRange();
range.selectNodeContents(el);
sel = window.getSelection();
sel.removeAllRanges();
sel.addRange(range);
}
}
selectElementContents( document.getElementById("someElement") );