JQuery search in static HTML page with highlighting of found word
I've been trying to make a simple search inside a static HTML page using JQuery. I have to mention that this is just my first time working with JQuery.
I'm trying to change the background of the found word in the page and this is what I've tried so far:
myJavascript.js:
$(document).ready(function(){
$('#searchfor').keyup(function(){
page = $('#all_text').text();
searchedText = $('#searchfor').val();
$("p:contains('"+searchedText+"')").css("color", "white");
});
});
Here's the HTML code as well:
page.html:
<html>
<head>
<title>Test page</title>
</head>
<body bgcolor="#55c066">
<input type="text" id="searchfor"></input>
<p id="all_text">Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euism modo typi, qui nunc nobis videntur parum clari, fiant sollemnes in futurum.
<font color="red">Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tinci futurum.</font>
</p>
</body>
<script src="jquery-1.7.2.min.js"></script>
<script src="myJavascript.js"></script>
</html>
After inspecting the page with Firebug I can see that the variables in JQuery do get the value from the input field but I guess I'm messing up the highlighting part.
Thanks in advance for your help!
Answer
Why using a selfmade highlighting function is a bad idea
The reason why it's probably a bad idea to start building your own highlighting function from scratch is because you will certainly run into issues that others have already solved. Challenges:
- You would need to remove text nodes with HTML elements to highlight your matches without destroying DOM events and triggering DOM regeneration over and over again (which would be the case with e.g.
innerHTML) - If you want to remove highlighted elements you would have to remove HTML elements with their content and also have to combine the splitted text-nodes for further searches. This is necessary because every highlighter plugin searches inside text nodes for matches and if your keywords will be splitted into several text nodes they will not being found.
- You would also need to build tests to make sure your plugin works in situations which you have not thought about. And I'm talking about cross-browser tests!
Sounds complicated? If you want some features like ignoring some elements from highlighting, diacritics mapping, synonyms mapping, search inside iframes, separated word search, etc. this becomes more and more complicated.
Use an existing plugin
When using an existing, well implemented plugin, you don't have to worry about above named things. The article 10 jQuery text highlighter plugins on Sitepoint compares popular highlighter plugins. This includes plugins of answers from this question.
Have a look at mark.js
mark.js is such a plugin that is written in pure JavaScript, but is also available as jQuery plugin. It was developed to offer more opportunities than the other plugins with options to:
- search for keywords separately instead of the complete term
- map diacritics (For example if "justo" should also match "justò")
- ignore matches inside custom elements
- use custom highlighting element
- use custom highlighting class
- map custom synonyms
- search also inside iframes
- receive not found terms
Alternatively you can see this fiddle.
Usage example:
// Highlight "keyword" in the specified context
$(".context").mark("keyword");
// Highlight the custom regular expression in the specified context
$(".context").markRegExp(/Lorem/gmi);
It's free and developed open-source on GitHub (project reference).
Example of mark.js keyword highlighting with your code
$(function() {
$("input").on("input.highlight", function() {
// Determine specified search term
var searchTerm = $(this).val();
// Highlight search term inside a specific context
$("#context").unmark().mark(searchTerm);
}).trigger("input.highlight").focus();
});mark {
background: orange;
color: black;
}<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdn.jsdelivr.net/mark.js/7.0.0/jquery.mark.min.js"></script>
<input type="text" value="test">
<div id="context">
Lorem ipsum dolor test sit amet
</div>