jquery自定义下拉列表调用方法

(function($){
 var option={
isedit:false,  //是否可以编辑:默认是否
Listheight:200,  //下拉框高度
ListWidth:0,//下拉框长度
//数据源
data:[
 {"value":1,"text":"选择1"},
 {"value":2,"text":"选择2"},
 {"value":3,"text":"选择3"},
 {"value":4,"text":"选择4"}
 ]
}
//创建下拉框
function Start(obj)
{
    if(!option.isEdit)
    {
    obj.attr({"readonly":"readonly"});
}
var myList=$("<div></div>");
var  ul=$("<ul></ul>");
ul.css({"list-style":"none","margin":"0px","padding":"2px"});
myList.css({"border":"1px solid #D9E5F3","position":"absolute","overflow-y":"scroll","background-color":"#fff","font-size":"12px"});
if(option.Listheight<=0)
{
option.Listheight=200;
}
myList.height(option.Listheight);
if(option.ListWidth<=0)
{
   option.ListWidth=obj.width()
 }
myList.width(option.ListWidth);
//默认位置是在创建元素的下方
myList.offset({"top":obj.offset().top+obj.outerHeight(),"left":obj.offset().left});
var data=option.data;

if(data.length>0)
{
for(i=0;i<data.length;i++)
{
   var li=$("<li/>");
    var ListSon=$("<input type='checkbox' />");
   ListSon.change(function(){
if(this.checked)   
{
    obj.val(obj.val()+$(this).val());
}
else
{
    obj.val(obj.val().replace($(this).val(),""));
}
 })
    myList.mouseover(function(){
   myList.show();
    })
   myList.mouseout(function(){
   myList.hide();
    })
   var span=$("<span></span>");
   span.text(data[i].text);
ListSon.val(data[i].value+";");
    li.append(ListSon);
   li.append(span);
   ul.append(li);
}
 }
   myList.append(ul);
myList.appendTo("body");
   myList.hide();

  FoucsShow($(obj),myList);
}
// 当获取到焦点使出现该下拉框
function FoucsShow(obj,myList)
{
    obj.focus(function(){myList.show()})
}
$.fn.createList=function(newoption)
{
    $.extend(option,newoption);
   Start($(this));

}
})(jQuery);

$("#d2").createList({
//数据源
data:[
 {"value":"C#","text":"C#"},
 {"value":".NET","text":".NET"},
 {"value":"Java","text":"Java"},
 {"value":"JSP","text":"JSP"},
 {"value":"C","text":"C"},
 {"value":"C++","text":"C++"},
 {"value":"javascript","text":"javascript"},
 {"value":"ajax","text":"ajax"},
 {"value":"json","text":"json"},
 {"value":"xml","text":"xml"},
 {"value":"sql server","text":"sql server"},
 {"value":"xml","text":"mysql"},
 {"value":"oracle","text":"oracle"},
 {"value":"JQuery","text":"JQuery"},
 {"value":"Ext js","text":"Ext js"},
 {"value":"CSS3","text":"CSS3"},
 {"value":"HTML5","text":"HTML5"}
 ]   
  });
  $("#d3").createList();   
})