var httpReqObj = makeAjxObj();

function makeAjxObj () {
	if (window.ActiveXObject) {
		return new ActiveXObject("Microsoft.XMLHTTP");
		
	} else if (window.XMLHttpRequest) {	
		return  new XMLHttpRequest();
	} else {
		alert("Your browser does not support AJAX.");
	} 
}

function doIt() {
	
	var selectVal = document.getElementById("file_type").value;
	var params = "search=" + document.getElementById('searchId').value + "&file_type=" + selectVal;

	
	if ( httpReqObj  != null ) {
		httpReqObj.open("POST" , "./search_site.php" , true );
		params.length = params.length + 1;
		httpReqObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
		httpReqObj.setRequestHeader("Content-length", params.length);
		httpReqObj.setRequestHeader("Connection", "close");
		httpReqObj.send(params);
		
		
		httpReqObj.onreadystatechange = function () {
			if ( httpReqObj.readyState == 4 ) {
				document.getElementById("searchOutput").innerHTML = httpReqObj.responseText;
				
			}
		}
	}
	
			
	
}