function GetXmlHttpObject() {
    var xmlHttp=null;
    try  {
     // Firefox, Opera 8.0+, Safari
     xmlHttp=new XMLHttpRequest();
     }
    catch (e) {
     // Internet Explorer
     try   {
      xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
      }
     catch (e) {
      xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
      }
     }
return xmlHttp;
}
          var xmlHttp
function sentsms() {
         var name =document.getElementById("txt_name").value;
         var email=document.getElementById("txt_email").value
         var interest=document.getElementById("sel_interest").value;
         var phoneno=document.getElementById("txt_phone").value;
         var reference=document.getElementById("sel_reference").value;
         var msg=document.getElementById("txt_comments").value;
         
		     var numericExpression = /^[0-9]+$/;
		     
         if ((name==null)||(name=="")){
        		alert("Please Enter your Name");
        		document.getElementById("txt_name").focus()
        		return false
        	} 
         else if ((phoneno=="") || (phoneno==" ") || (!(phoneno.match(numericExpression)))) {
    			 alert('Enter The Phone Number And Only Numbers');
    			 document.getElementById("txt_phone").focus();
    			 return false;		 
         } 
		     else {
                xmlHttp=GetXmlHttpObject()
                if (xmlHttp==null) {
                   alert ("Browser does not support HTTP Request")
                   return
                }  
                else {
                   xmlHttp.open("POST","mailsent.php",true); //calling mailsent.php using POST method
                   xmlHttp.onreadystatechange  = handleServerResponsemail;
                   xmlHttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
                   xmlHttp.send("&name="+name+"&interest="+interest+"&email="+email+"&ref="+reference+"&phoneno="+phoneno+"&msg="+msg); //Posting txtname to PHP File
                }
         }
}
function handleServerResponsemail() {
    if(xmlHttp.readyState == 1){      
      document.getElementById("mail").innerHTML="Message and Mail sending...";      
    }
   if ((xmlHttp.readyState == 4) && (xmlHttp.status == 200)) {
       document.getElementById("mail").innerHTML=xmlHttp.responseText; //Update the HTML Form element
       document.getElementById("txt_name").value="";
       document.getElementById("txt_phone").value=""; 
       document.getElementById("txt_email").value="";
       document.getElementById("txt_comments").value="";      
     } 
     else {
       document.getElementById("txt_name").value="";
       document.getElementById("txt_phone").value=""; 
       document.getElementById("txt_email").value="";
       document.getElementById("txt_comments").value="";
     }   
  
}