// JavaScript Document
function checkForm(){
                 theform=document.feed_back
				  if (theform.name.value==""){ 
                     alert("Full Name is required")
                     theform.name.focus()
                     return false;
                }
				if (theform.country.selectedIndex=="0"){ 
                     alert("Select Your Country name.")
                     theform.country.focus()
                     return false;
                }
				
				    if (theform.zip.value==""){ 
                     alert("ZIP code is required")
                     theform.zip.focus()
                     return false;
                }
                  
                     if (theform.email.value==""){ 
                     alert("email address is required")
                     theform.email.focus()
                     return false;
                }
				 if (theform.address.value==""){ 
                     alert("Address is required")
                     theform.address.focus()
                     return false;
                }
				if (theform.phone.value==""){ 
                     alert("Phone is required")
                     theform.phone.focus()
                     return false;
                }							
                    
     // Check that the form has an email specified in the field called "email"
var emailaddress = theform.email.value;
var emailexp = /^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*\.(([a-z]{2,3})|(aero|coop|info|museum|name))$/i;
if (!emailexp.test(emailaddress)) { 
alert('Email address is missing or invalid, please check your email address')
theform.email.focus();
return false;
}
                    
                

<!--
//Validate Emai
function isEmail(strFieldName,strMsg)
{
     var strEmail = strFieldName.value;
     var bolValid = true;
     if(strEmail.length == 0){
          bolValid = false;
     }
     if(strEmail.length < 7){
          bolValid = false;
     }
     if(strEmail.lastIndexOf(" ") >0){
          bolValid = false;
     }
     var intLastDot = strEmail.lastIndexOf(".")
     if(intLastDot == -1 ||  strEmail.length - intLastDot >4){
          bolValid = false;
     }
     var intAt = strEmail.lastIndexOf("@")
     if(intAt == -1 ||  strEmail.length - intAt < 5){
          bolValid = false;
     }
     if(! bolValid){
          alert(strMsg.toUpperCase() +" is either empty or is not in the correct format");
               strFieldName.focus();
               }
     return bolValid;
}
function validateForm(fObj){
     if(!isEmail(fObj["email"],"email")){
          return false;
     }
     return true;
}

}