Does IE7 not fully support javascript's insertBefore method?

I have the following code which wor开发者_开发知识库ks perfect in Chrome, IE8, and FF. However, I get an error when I'm testing it with IE7. Does anyone have a clue what's happening here?

 function do_replace(s, p1,p2,p3,child_node,syn_text) {
       reg = new RegExp('[h\|H][1-7]');
   if(p1.length>0){   //this might not be necessary
     //create textnode
      var text_node = document.createTextNode(p1);
          child_node.parentNode.insertBefore(text_node,child_node);  //errors out here in IE7
       }

The code errors out at the last line- IE7 give an "htmlfile: Invalid argument." error when I look at the code through a debugger. child_node, parentNode, and text_node appear to be formed identical to Firefox and Chrome when running this script.

Any ideas? Or does IE7 just not support this method as well as other browsers?

Thanks

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Rather than leave this problem unsolved, I figured out what was wrong with my code:

I was using an extensive frameset(yuck!!) and when I made the text_node = document.createTextNode() call, I was not doing this in the frame that my application was in.

I fixed this by explicitly calling out the frame to create the object in:

var text_node = MainFrame.child_frame.WhySoManyFrames.document.createTextNode(p1);

After doing this, the insertBefore method works perfect!

Hopefully this helps anyone looking at this question- I know this took me a long time and lots of frustration to figure out!

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JavaScript 'InsertBefore' function is supported by IE7. Remember that you have to use this function only when page is fully loaded!

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