How to clear a read only jQuery date picker textbox?

Question

We have a JQuery date picker control on a read only text box. We make the textbox read only so users can't enter their own dates. This works great but we want to provide the users the option to clear out the contents of the text box after they have selected a date.

How can you do this? Apparently this functionality used to be built into the control but was removed.

Note: we disable input into the textbox using:

$("#text-box").keypress(function (e)
{
    e.preventDefault();
});

---

Update: I solved this with a slight variation of the selected answer:

    myTextBox.keydown(function(e){
        if (e.keyCode == 46 || e.keyCode == 8) {
            //Delete and backspace clear text 
            $(this).val(''); //Clear text
            $(this).datepicker("hide"); //Hide the datepicker calendar if displayed
            $(this).blur(); //aka "unfocus"
        }

        //Prevent user from manually entering in a date - have to use the datepicker box
        e.preventDefault();
    });

Answer 1

How about excluding keys thats user use to clear textbox like 'del', 'backspace' etc.?

$("#text-box").keypress(function (e)
{
  switch(e.keyCode) { 
          case 46:  // delete
          case 8:  // backspace
            break;
          default:
            e.preventDefault();
            break;
       }
});