No doubt very simple question for someone with php knowledge.

I have a form with a datepicker, all is fine when a user has selected a date the email is send with:

Date: 2012 04 10

But i would like if the user has skipped this and left blank (as i have not made this required) to send as:

Date: Not Entered (<-- Or something)

Instead at the minute of course it reads:

Date:

Form input

<input type="text" class="form-control" id="datepicker" name="datepicker" size="50" value="Date Of Wedding" />

This is the validator

$(document).ready(function(){

//validation contact form
$('#submit').click(function(event){
    event.preventDefault();

    var fname = $('#name').val();
    var validInput = new RegExp(/^[a-zA-Z0-9\s]+$/);
    var email = $('#email').val();
    var validEmail = new RegExp(/^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/);
    var message = $('#message').val();

    if(fname==''){ showError('<div class="alert alert-danger">Please enter your name.</div>', $('#name')); $('#name').addClass('required'); return;}
    if(!validInput.test(fname)){ showError('<div class="alert alert-danger">Please enter a valid name.</div>',  $('#name')); $('#name').addClass('required'); return;}
    if(email==''){ showError('<div class="alert alert-danger">Please enter an email address.</div>', $('#email')); $('#email').addClass('required'); return;}
    if(!validEmail.test(email)){ showError('<div class="alert alert-danger">Please enter a valid email.</div>', $('#email')); $('#email').addClass('required'); return;}
    if(message==''){ showError('<div class="alert alert-danger">Please enter a message.</div>', $('#message')); $('#message').addClass('required'); return;}

    // setup some local variables
    var request;
    var form = $(this).closest('form');

    // serialize the data in the form
    var serializedData = form.serialize();

    // fire off the request to /contact.php
    request = $.ajax({
        url: "contact.php",
        type: "post",
        data: serializedData
    });

    // callback handler that will be called on success
    request.done(function (response, textStatus, jqXHR){
        $('.contactWrap').show( 'slow' ).fadeIn("slow").html(' <div class="alert alert-success centered"><h3>Thank you! Your message has been sent.</h3></div> ');
    });

    // callback handler that will be called on failure
        request.fail(function (jqXHR, textStatus, errorThrown){
        // log the error to the console
        console.error( "The following error occured: "+ textStatus, errorThrown );
    });

});

//remove 'required' class and hide error
$('input, textarea').keyup( function(event){
    if($(this).hasClass('required')){
        $(this).removeClass('required');
        $('.error').hide("slow").fadeOut("slow");
    }
});

// show error
showError = function (error, target){
    $('.error').removeClass('hidden').show("slow").fadeIn("slow").html(error);
    $('.error').data('target', target);
    $(target).focus();
    console.log(target);
    console.log(error);
    return;
}

});