Search and Highlight in jQuery

http://jsfiddle.net/UPs3V/291/

 var src_str = $("#test").text();
var term = "my text";
term = term.replace(/(\s+)/,"(<[^>]+>)*$1(<[^>]+>)*");
var pattern = new RegExp("("+term+")", "gi");

src_str = src_str.replace(pattern, "<mark>$1</mark>");
src_str = src_str.replace(/(<mark>[^<>]*)((<[^>]+>)+)([^<>]*<\/mark>)/,"$1</mark>$2<mark>$4");

$("#test").html(src_str);

try this one it may help you

Try this out:- http://jsfiddle.net/adiioo7/H7CqV/

You need to remove the b tags from div1 and in order to apply bold property you can use css property font-weight:bold.

HTML:-

<div id="div1" style="font-weight:bold">Good Morning</div>
<div id="div2">Good Evening</div> 
<div id="div3">Good Morning</div>

or

<div id="div1"><b>Good Morning</b></div>
<div id="div2">Good Evening</div> 
<div id="div3">Good Morning</div>

JS:-

$("body").highlight("Good Morning");

Edit: highlight is a 3rd party jquery lib, more info here: http://johannburkard.de/blog/programming/javascript/highlight-javascript-text-higlighting-jquery-plugin.html

demo

script

jQuery.fn.highlight = function(pat) {
 function innerHighlight(node, pat) {
  var skip = 0;
  if (node.nodeType == 3) {
   var pos = node.data.toUpperCase().indexOf(pat);
   if (pos >= 0) {
    var spannode = document.createElement('span');
    spannode.className = 'highlight';
    var middlebit = node.splitText(pos);
    var endbit = middlebit.splitText(pat.length);
    var middleclone = middlebit.cloneNode(true);
    spannode.appendChild(middleclone);
    middlebit.parentNode.replaceChild(spannode, middlebit);
    skip = 1;
   }
  }
  else if (node.nodeType == 1 && node.childNodes && !/(script|style)/i.test(node.tagName)) {
   for (var i = 0; i < node.childNodes.length; ++i) {
    i += innerHighlight(node.childNodes[i], pat);
   }
  }
  return skip;
 }
 return this.each(function() {
  innerHighlight(this, pat.toUpperCase());
 });
};

jQuery.fn.removeHighlight = function() {
 function newNormalize(node) {
    for (var i = 0, children = node.childNodes, nodeCount = children.length; i < nodeCount; i++) {
        var child = children[i];
        if (child.nodeType == 1) {
            newNormalize(child);
            continue;
        }
        if (child.nodeType != 3) { continue; }
        var next = child.nextSibling;
        if (next == null || next.nodeType != 3) { continue; }
        var combined_text = child.nodeValue + next.nodeValue;
        let new_node = node.ownerDocument.createTextNode(combined_text);
        node.insertBefore(new_node, child);
        node.removeChild(child);
        node.removeChild(next);
        i--;
        nodeCount--;
    }
 }

 return this.find("span.highlight").each(function() {
    var thisParent = this.parentNode;
    thisParent.replaceChild(this.firstChild, this);
    newNormalize(thisParent);
 }).end();
};

HTML

Search: <input type="text" id="text-search" />

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<script type="text/javascript">
$(function() {
    $('#text-search').bind('keyup change', function(ev) {
        // pull in the new value
        var searchTerm = $(this).val();

        // remove any old highlighted terms
        $('body').removeHighlight();

        // disable highlighting if empty
        if ( searchTerm ) {
            // highlight the new term
            $('body').highlight( searchTerm );
        }
    });
});
</script>