function ValidateForm()
{
    UserNameValue = trim(document.getElementById("txtUserName").value);
    PasswordValue = trim(document.getElementById("txtPassword").value);
    
    UserNameValidator = document.getElementById("rfvUserName");
    PasswordValidator = document.getElementById("rfvPassword");
    
    UserNameValidator.innerHTML = "";
    PasswordValidator.innerHTML = "";
    
    if (UserNameValue == "")
    {
        UserNameValidator.style.visibility = "visible";
        UserNameValidator.innerHTML = "<br />* User name is required.";
    }
    
    if (PasswordValue == "")
    {
        PasswordValidator.style.visibility = "visible";
        PasswordValidator.innerHTML = "<br />* Password is required.";
    }
	
	document.getElementById("lblMessage").innerHTML = "";
    
    return (UserNameValue != "" && PasswordValue != "");
}