$("#saveBttn").one("click", function () {
alert("This will be displayed only once.");
});

$("body").one("click", "#saveBttn", function () {
alert("This displays if #saveBttn is the first thing clicked in the body.");
});上述代碼關鍵在于：

$("#saveBttn").on("click", function (event) {
alert("This will be displayed only once.");
$(this).off(event);
});