function showHint(str)

{

if (str.length==0)

{ 

document.getElementById("txtHint").innerHTML=""

return

}

xmlHttp=GetXmlHttpObject()

if (xmlHttp==null)

{

alert ("Browser does not support HTTP Request")

return

} 

var url="available.php"

url=url+"?q="+str

url=url+"&sid="+Math.random()

xmlHttp.onreadystatechange=stateChanged 

xmlHttp.open("GET",url,true)

xmlHttp.send(null)

}

function stateChanged() 

{ 

if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")

{ 

document.getElementById("txtHint").innerHTML=xmlHttp.responseText 

} 

} 

function GetXmlHttpObject(handler)

{ 

var objXMLHttp=null

if (window.XMLHttpRequest)

{

objXMLHttp=new XMLHttpRequest()

}

else if (window.ActiveXObject)

{

objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP")

}

return objXMLHttp

}