function ValidateForm()
{
    if(document.getElementById("FirstNameTextBox").value=="")
    {
        ShowMessage("Your First Name is required");
        return false;
    }
    if(document.getElementById("LastNameTextBox").value=="")
    {
        ShowMessage("Your Last Name is required");
        return false;
    }
    if(document.getElementById("EmailTextBox").value=="")
    {
        ShowMessage("Your Email is required");
        return false;
    }
        
    if(!checkMail(document.getElementById("EmailTextBox").value))
    {
        ShowMessage("Valid Email is required");
        return false;
    }
            
    if(document.getElementById("SendButton")!=null)
    {
        document.getElementById("SendButton").click();
    }
}