function dwComboboxSearch(dwMode){
	//http://dianielsen.thomasnet.com/keyword/all-categories?&key=all&keycateg=100&keyprod=&SchType=2&keyword=
	var dwText;
	switch(dwMode)
	{
	case 1:
		dwText = document.formManufacturerOEM.selectManufacturerOEM.options[document.formManufacturerOEM.selectManufacturerOEM.options.selectedIndex].text;
	  break;    
	case 2:
		dwText = document.formRecorderModel.selectRecorderModel.options[document.formRecorderModel.selectRecorderModel.options.selectedIndex].text;
	  break;
	default:
		dwText = document.formProductType.selectProductType.options[document.formProductType.selectProductType.options.selectedIndex].text;
	}
	if ((dwText != "Recorder Model")&&(dwText != "Manufacturer / OEM") && (dwText != "Product Type") ){
	  url = "http://dianielsen.thomasnet.com/keyword/?&plpver=10&key=all&keycateg=100"
	  url = url + "&SchType=2";
	  url = url + "&keyword=" + encodeURI(dwText);
	  url = url + "&refer=" + encodeURI("http://" + document.location.hostname);	
	  
	  document.location.href = url;
	} else{
		alert("Please choose an item in the drop down box");
	}
}


function dwKeywordSearchP()
{
 var url;
 var theform = document.formKeywordSearch;

 if ((theform.dwKeywordSearch.value.length < 2) || (theform.dwKeywordSearch.value == "Keyword Search"))
 {
  alert('Please enter at least two characters.');
  theform.dwKeywordSearch.focus();
 }
 else
 {
// Version 2.7 release
// 1. using default Domain, like "orientalmotor.thomasnet.com" in our sample
// 2. using root category shortName, like "all-categories" in our sample
  url = "http://dianielsen.thomasnet.com/keyword/?&plpver=10&key=all&keycateg=100"
  url = url + "&SchType=2";
  url = url + "&keyword=" + encodeURI(theform.dwKeywordSearch.value);
  url = url + "&refer=" + encodeURI("http://" + document.location.hostname);

  document.location.href = url;
 }
//alert (url);
}


function dwPartNumberSearchP()
{
 var url;
 var theform = document.formPartNumberSearch;

 if ((theform.dwPartNumberSearch.value.length < 2) || (theform.dwPartNumberSearch.value == "Dia-Nielsen Part Number"))
 {
  alert('Please enter at least two characters.');
  theform.dwPartNumberSearch.focus();
 }
 else
 {
// Version 2.7 release
// 1. using default Domain, like "orientalmotor.thomasnet.com" in our sample
// 2. using root category shortName, like "all-categories" in our sample
  url = "http://dianielsen.thomasnet.com/keyword/?&plpver=10&key=all&keycateg=100"
  url = url + "&SchType=1";
  url = url + "&keyword=" + encodeURI(theform.dwPartNumberSearch.value);
  url = url + "&refer=" + encodeURI("http://" + document.location.hostname);

  document.location.href = url;
 }
//alert (url);
}


function emptyField(thisField) {
	if (thisField.defaultValue == thisField.value) thisField.value = "";
}
function fillField(thisField) {
	if (thisField.value == "") thisField.value = thisField.defaultValue;
}

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function correctPNG() // correctly handle PNG transparency in Win IE 5.5 & 6.
{
   var arVersion = navigator.appVersion.split("MSIE")
   var version = parseFloat(arVersion[1])
   if ((version >= 5.5) && (document.body.filters)) 
   {
      for(var i=0; i<document.images.length; i++)
      {
         var img = document.images[i]
         var imgName = img.src.toUpperCase()
         if (imgName.substring(imgName.length-3, imgName.length) == "PNG")
         {
            var imgID = (img.id) ? "id='" + img.id + "' " : ""
            var imgClass = (img.className) ? "class='" + img.className + "' " : ""
            var imgTitle = (img.title) ? "title='" + img.title + "' " : "title='" + img.alt + "' "
            var imgStyle = "display:inline-block;" + img.style.cssText 
            if (img.align == "left") imgStyle = "float:left;" + imgStyle
            if (img.align == "right") imgStyle = "float:right;" + imgStyle
            if (img.parentElement.href) imgStyle = "cursor:hand;" + imgStyle
            var strNewHTML = "<span " + imgID + imgClass + imgTitle
            + " style=\"" + "width:" + img.width + "px; height:" + img.height + "px;" + imgStyle + ";"
            + "filter:progid:DXImageTransform.Microsoft.AlphaImageLoader"
            + "(src=\'" + img.src + "\', sizingMethod='scale');\"></span>" 
            img.outerHTML = strNewHTML
            i = i-1
         }
      }
   }    
}
window.attachEvent("onload", correctPNG);
<!--[endif]-->