easy ui 下拉框绑定事件

---------------选择改变------------------------------

<input id='ServiceStatus' field-type='combo' type='text' class='easyui-combobox' style=' 100px' value=''
data-options=" valueField: 'id', textField: 'text',url: '../../Ajax/GetListData.ashx?DataType=Code&ParamValue=ServiceStatus',
onChange:ServiceStatusChange
" />

--------------下拉框级联绑定----------------------------

<div class="input_item_div">
<input id='ProvinceID' name='ProvinceID' field-type='text' type='text' class='easyui-combobox' style=' 150px' value='9' data-options="valueField: 'id', textField: 'text',url: '../../Ajax/ListProvince.ashx',onSelect: function(rec){
var url = '../../Ajax/ListCity.ashx?ProvinceID='+rec.id;
$('#CityID').combobox('reload', url);
$('#CityID').combobox('setValue','');
}" />
</div>
<div class='label inputSize20'>省</div>
<div class="input_item_div">
<input id='CityID' name='CityID' field-type='text' type='text' class='easyui-combobox' style=' 150px' value='' data-options="valueField: 'id', textField: 'text',url: '../../Ajax/ListProvince.ashx'" />
</div>
<div class='label inputSize20'>市</div>