Question

I currently am trying to add tags around certain words in a webpage. This webpage can have many different id’s, classes, and names, so it’s important that if I’m trying to put a span around “foo” I do the following:

<p class='foo'>blah blah blah foo blah blah blah </p>

changes into

<p class='foo'>blah blah blah <span class='bar'> foo </span> blah blah blah </p>

and not

<p class='<span class='bar'> foo </span>'>blah blah blah <span class='bar'> foo </span> blah blah blah </p>

I’m investigating parsing the website out using the following code:

var obj = $(this.innerHTML);  //in my selector which selects the part of the website I want to apply the span to

I’m able to browse this data structure in firebug, but modifying it (or searching it) is proving to be more difficult.

If I look at obj[1], the innerHTML property looks like this:

<h4 id="3423df" class="pzCMD">blah blah foo blah </h4>

I have no idea how to modify this element (if possible) or add new nodes to it. I can extract the “text” by looking at the textContent

obj[1].textContent = blah blah foo blah

but I’m unsure how I would go about changing the html code of this element to

<h4 id="3423df" class="pzCMD">blah blah <span class='bar' foo <span> blah </h4>

Thanks for any help, sorry for the long drawn out explanation.

Answer 1

I was attempting to do this in the wrong way. Here is the solution that I created, and seems to work great. It uses two recursive functions + DOM traversal + regular expressions to create the proper text and span nodes.

function replaceText(element, pattern, syn_text) {

for (var childi = 0; childi < element.childNodes.length;childi++) {
    var child= element2.childNodes[childi];
    if (child.nodeType==1 && child.className!=syn_text){ //make sure we don't call function on newly created node
        replaceText(child, pattern, syn_text);  //call function on child
    }
    else if (child.nodeType==3){ //this is a text node, being processing with our regular expression
        var str = child.data;
        str = str.replace(pattern,function(s, p1,p2,p3) {
            var parentNode = child.parentNode;
            do_replace(s, p1,p2,p3,parentNode,pattern,syn_text);
            parentNode.removeChild(child);  //delete old child from parent node.  we've replaced it with new nodes at this point
         });
    }
}}




function do_replace(s, p1,p2,p3,parentNode,pattern,syn_text) {
   if(p1.length>0){   //this might not be necessary
     //create textnode
      var text_node = document.createTextNode(p1);
      parentNode.appendChild(text_node);
   }
   if(p2.length > 0){ //create a span + next_node for the highlighting code
      spanTag = document.createElement("span");
      spanTag.id = "SString" + id++;
      spanTag.className = syn_text;
      spanTag.innerHTML = p2;
      parentNode.appendChild(spanTag);
   }
   if(p3.length > 0){
       //test to see if p3 contains another instance of our string.

      if(pattern.test(p3)){  //if there is a instance of our text string in the third part of the string, call function again
          p3.replace(pattern,function(s, p1,p2,p3) {
            //debugger;
            do_replace(s, p1,p2,p3,parentNode,pattern);
            return;
          });
      }
      else{  //otherwise, it's just a plain textnode, so just reinsert it.
          var text_nodep3 = document.createTextNode(p3);
          parentNode.appendChild(text_nodep3);
          return;
      }
    }
    else{ //does this do anything?
        return;
     }
return}

This function is called as follows:

syn_highlight = "highlight_me";  //class to signify highlighting 
pattern = new RegExp('([\\w\\W]*?)\\b('+ searchTerm + '[\\w]*)\\b([\\w\\W]*)',"ig");
replaceText($('#BodyContent')[0],pattern,syn_highlight);