function isEmail(string) {
if (string.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
return true;
else
return false;
}



String.prototype.trim = function () {
    return this.replace(/^\s*/, "").replace(/\s*$/, "");
}



function validateForm(){
    var email = document.getElementById('txtEmail').value.trim();
     if(!isEmail(email)){
        alert("Please enter a valid email address");
        document.getElementById('txtEmail').focus();
        return false;
	 }
    else{
        return true;
    }
    
}