Question

I have:

 if (xmlhttp.readyState==4 && xmlhttp.status==200)
     {

    cu=$("#box1").val();
    cur=xmlhttp.responseText;

    cur=cur.replace(cu,'<strong>'+cur+'</strong>');  

     $(".box2").html(cur);

 }

I try that, and the replace just doesn’t happen.

When I change cur to just have a value of normal text (cur='my name is....';) then it works fine.

I’ve tried changing the replace line to: cur=cur.replace(cu,'found it'); – still nothing

This is all in the same function as the where the AJAX request takes place…

Any ideas?

Answer 1

Your code works if you fix one issue that may be a copy and paste error. You are setting .html(current_response), but current_response is never defined.

http://jsfiddle.net/4LXWd/1/

But I doubt it works the way you want it to. If $("#box1").val() is world and xmlhttp.responseText is hello world hello world, your result will only replace the first instance of world, and it will replace it with the entire response string, so you’ll get:

hello <strong>hello world hello world</strong> hello world

Is that what you want? If only replacing the first instance of the matched string is fine, you probably want this:

cur = cur.replace(cu, "<strong>$&</strong>");

Edit: But to replace every instance of the matched string, you’ll need to use a regular expression:

cu = $("#box1").val();
var re = new RegExp(cu.replace(/[\[\]\\.*+?^${}()\/|]/g, "\\$&"), "g");
cur = xmlhttp.responseText;
cur = cur.replace(re, '<strong>$&</strong>');
$(".box2").html(cur);

Working demo: http://jsfiddle.net/4LXWd/2/