var weatherHTTP;
var weatherxmlDoc;
function IsNumeric(sText)
{
   var ValidChars = "0123456789";
   var IsNumber=true;
   var Char;

 
   for (i = 0; i < sText.length && IsNumber == true; i++) 
      { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1) 
         {
         IsNumber = false;
         }
      }
   return IsNumber;
   
   }
function getWeather(str) {
  if(str.length==5 && IsNumeric(str)){
  
	weatherHTTP = false;
    // branch for native XMLHttpRequest object
    if(window.XMLHttpRequest && !(window.ActiveXObject)) {
    	try {
			weatherHTTP = new XMLHttpRequest();
        } catch(e) {
			weatherHTTP = false;
        }
    // branch for IE/Windows ActiveX version
    } else if(window.ActiveXObject) {
       	try {
        	weatherHTTP = new ActiveXObject("Msxml2.XMLHTTP");
      	} catch(e) {
        	try {
          		weatherHTTP = new ActiveXObject("Microsoft.XMLHTTP");
        	} catch(e) {
          		weatherHTTP = false;
        	}
		}
    }
	if(weatherHTTP) {
		weatherHTTP.onreadystatechange = processReqChange;
		weatherHTTP.open("GET", "weather.php", true);
		weatherHTTP.send();
	} else {
	 document.getElementById("WeatherHolder").innerHTML = "The security settings of your browser are preventing the retrieval of the local weather.<br /><br />If you wish to view the weather display please adjust your browser security settings to allow for external content and active X controls to be utilized, then refresh the page."
	}
	} else {
	 alert("Zip codes must be 5 characters and only numbers");
	}
}
function processReqChange() {
  var content = "";
  // only if req shows "loaded"
  if (weatherHTTP.readyState == 4) {
	 // only if "OK"
	  if (weatherHTTP.status == 200) {
		 if (weatherHTTP.responseText.indexOf('<!-- SUCCESS -->') != -1){    
			document.getElementById("WeatherHolder").innerHTML = weatherHTTP.responseText;  
			//alert(content);
		 } else {  
			// Tell the reader that there was error requesting data  
			 document.getElementById("WeatherHolder").innerHTML = "We apologize, an error has occurred in the weather retrieval system.  Please check back with the system later.";  		 }  
	  } else {
			 document.getElementById("WeatherHolder").innerHTML = "We apologize, an error has occurred in the weather retrieval system.  Please check back with the system later.";   
	 } 
  }
}