Disable/enable element with checkbox and jQuery?

Question

I have a checkbox and if I tick it I want a textfield to become enabled (disabled as default) and when I untick the the checkbox I want it to become disabled again.

Answer 1

show and hide a textbox(#otherSection2) for entering other options when last checkbox in a rendered table(#CheckBoxListList) of asp:CheckBoxList control is selected

 $("#CheckBoxListList input[type='checkbox']:last").on("click", function () {

                if ($(this).is(":checked")) {
                    $("#otherSection2").show();
                } else {
                    $("#otherSection2").hide().find("input").val(null);

                }
            });