Hy  :D  i have one bho (browser helper object ) and i need to add this function in javascript

(

function () {
  var nova = document.getElementById('PartNumberTextBox');
  var so = document.getElementById('so_id');
  var newsn = document.getElementById('new_sn');
  var button = document.getElementById('book_button');
  var newpart = document.getElementById('new_part_no');
  document.body.onkeyup = function (e) {
  if (e === null) e = window.event;
  var code = e.keyCode || e.which;
  if (code == '9') {
  if (e.srcElement == newsn) {
  so.focus();
  } else if (e.srcElement == so) {
  button.focus();
  } else {
  nova.focus();
  }
  }
  };

  nova.onchange = novafunc;
  nova.onblur = novafunc;
  nova.onkeyup = novafunc;
  nova.onmouseup = novafunc;

  function novafunc() {
  if (newpart.value === nova.value && nova.value.length > 0) {
  nova.style.backgroundColor = '#0f0';
  newsn.focus();
  } else {
  nova.style.backgroundColor = '#f00';
  }
  }

})();

to a certain page using c#  ...  ... What's the best solution ?
The page just contains frameset and frames ... and i have used this method to add the textbox on the page ...

  IHTMLElement head= (IHTMLElement)((IHTMLElementCollection)document.all.tags("head")).item(null, 0);
  IHTMLScriptElement scriptObject =(IHTMLScriptElement)document.createElement("script");
  scriptObject.type = @"text/javascript";
  scriptObject.text = @"
 var inp = document.createElement('input');
  inp.id = 'PartNumberTextBox';
  inp.style.position = 'absolute';
  inp.style.right = '6px';
  inp.style.top = '435px';
  inp.style.width = '280px';
  inp.style.backgroundColor = '#000494';
var framex = window.frames;
for (var i = 0; i < framex.length; i++) {
  framex[i].document.body.appendChild(inp);
}";
  ((HTMLHeadElement)head).appendChild((IHTMLDOMNode)scriptObject);

can you please help me to add the javascript on the page ? thanks