how to stop javascript function after running once?

Question

can someone please show me how i can stop this javascript function after it has ran once? At the moment it just repeats again and again and i only want it to run the once.

I'm still learning javascript, so sorry if its not great.

thanks

<script>
$(function() {
 $(".search_prompt").hide();
 $("#text").focusin(function() {
 $(".search_prompt").show();
 }).focusout(function () {
 $(".search_prompt").hide();
 });
});
</script>

• David G: Can you make a jsFiddle?

Answer 1

<script>
$(function() {
 $(".search_prompt").hide();
 $("#text").one('focusin', function() {
 $(".search_prompt").show();
 }).one('focusout', function () {
 $(".search_prompt").hide();
 });
});
</script>

http://api.jquery.com/one/

Answer 2

Unbind the event handler once it has been run:

$(function() {
 $(".search_prompt").hide();
 function show_search_prompt() {
 $(".search_prompt").show();
 $("#text").unbind("focusin", show_search_prompt);
 }
 function hide_search_prompt() {
 $(".search_prompt").hide();
 $("#text").unbind("focusout", show_search_prompt);
 }
 $("#text").bind("focusin", show_search_prompt);
 $("#text").bind("focusout", hide_search_prompt);
});

Working example

http://jsfiddle.net/bikeshedder/JqErw/

---

JQuery plugin

If you need this several times you could write a JQuery plugin for this:

$.fn.bindRunOnce = function(eventType, eventHandler) {
 this.bind(eventType, function cb() {
 $(this).unbind(eventType, cb);
 eventHandler.apply(this, arguments);
 });
};
$(function() {
 $(".search_prompt").hide();
 $("#text").bindRunOnce("focusin", function(ev) {
 $(".search_prompt").show();
 });
 $("#text").bindRunOnce("focusout", function() {
 $(".search_prompt").hide();
 });
});

Live demo

http://jsfiddle.net/bikeshedder/JqErw/1/

---

... or you could use one as suggested by salexch.

How could I miss this one? :-)