function emailValidator(email){
	var emailArray = email.split(",");
	var emailFilter = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/; 
	var emailFlag = true;
	for(var i=0; i<emailArray.length; i++)	{		
		if (!emailFilter.test(emailArray[i].replace(/ /, ''))){
			emailFlag=false;
		}
	}
	return emailFlag;
}
//function for form validation
function validation() {
	errMsg = "Please provide required fields:"; 
        var flag = true;
	    if((document.getElementById('subject').value == "")) {
                errMsg +="\nSubject";
                flag = false;
        }   
        if((document.getElementById('name').value == "")) {
                errMsg +="\nFirst name";
                flag = false;
				//return false;
				
        }  
		if((document.getElementById('lname').value == "")) {
                errMsg +="\nLast name";
                flag = false;
				//return false;
        }   
		  if((document.getElementById('email').value== "")){
                errMsg +="\nEmail";
               flag = false;
				//return false;
				
        }       
		 if((document.getElementById('message').value == "")) {
                errMsg +="\nComments";
                flag = false;
				//return false;
        }   
//checking email field blank or not
       
//if email field not blank then checking either user given correct format of email id 
     if(flag == true){
		flag = emailValidator((document.getElementById('email').value));  
		if(flag==false) errMsg +="\nEnter valid email address";
	}
    if(flag == false) alert(errMsg);
	return flag;
}