JQUERY拖曳物件，並限制拖曳範圍

//拖曳參數

  $(function() {

    $( "#cvs" ).draggable({

        containment: "#box",

        scroll: false,

drag: function(event, ui) {

set_loc();

}

});

  });

<div id="box" style="position: absolute; left: -600px; top: -1200px; width:1800; height: 2800px;"> <div>