// Get the HTTP Object
function getHTTPObject(){
if (window.ActiveXObject) return new ActiveXObject("Microsoft.XMLHTTP");
else if (window.XMLHttpRequest) return new XMLHttpRequest();
else {
alert("Your browser does not support AJAX.");
return null;
}
}

// Change the value of the outputText field
function setOutput(){
if(httpObject.readyState == 4){
	alert("Your request was sumbitted.  Thanks!");
	 document.getElementById('txtEmail').value = "" 
}
} 
// Implement business logic
function submitForm(){

	if(ValidateForm())
 	{
		httpObject = getHTTPObject();
		if (httpObject != null) {
		httpObject.open("GET", "mail.php?txtEmail=" +document.getElementById('txtEmail').value  + "&carrier="+escape(document.getElementById('carrier').value), true);
		httpObject.send(null);
		httpObject.onreadystatechange = setOutput;
		}
	}

}
var httpObject = null;


// JavaScript Document
/**
 * DHTML email validation script. Courtesy of SmartWebby.com (http://www.smartwebby.com/dhtml/)
 */
var xmlHttp 
function echeck(str) {

		var at="@"
		var dot="."
		var lat=str.indexOf(at)
		var lstr=str.length
		var ldot=str.indexOf(dot)
		if (str.indexOf(at)==-1){
		   alert("Invalid E-mail ID")
		   return false
		}

		if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
		   alert("Invalid E-mail ID")
		   return false
		}

		if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		    alert("Invalid E-mail ID")
		    return false
		}

		 if (str.indexOf(at,(lat+1))!=-1){
		    alert("Invalid E-mail ID")
		    return false
		 }

		 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		    alert("Invalid E-mail ID")
		    return false
		 }

		 if (str.indexOf(dot,(lat+2))==-1){
		    alert("Invalid E-mail ID")
		    return false
		 }

		 if (str.indexOf(" ")!=-1){
		    alert("Invalid E-mail ID")
		    return false
		 }

 		 return true
	}

function ValidateForm(){
	var emailID=document.frmSample.txtEmail

	if ((emailID.value==null)||(emailID.value=="")){
		alert("Please Enter your Email ID")
		emailID.focus()
		return false
	}
	if (echeck(emailID.value)==false){
		emailID.value=""
		emailID.focus()
		return false
	}
	return true
 }