How to prevent repeat in jQuery function?

Have a variable (global) which says whether it has been loaded or not. E.g:

var loaded = false;
$('.button').click(function(){
   if(!loaded){
      $('#target').load('http://page');
      loaded = true;
   }
   $("#target").slideToggle();
});

This will cause the slideToggle to occur on every click, but the page to load only the once. :)

$('.button')
    .on('click.loadPage', function() {
        $("#target").load('http://page');
        $(this).off("click.loadPage");
    })
    .on('click.slideToggle', function(){
        $("#target").slideToggle();
    });

and another way without global vars:

$('.button')
    .on('click', function() {
        if ( !$(this).data("loaded") ) {
            $("#target").load('http://page');
            $(this).data("loaded", true);
        }
        $("#target").slideToggle();
    });