Easyui DataGrid combobox联动下拉框内容

发票信息下拉框联动，更具不同的发票类型，显示不同的税率

专票

普票

下拉框选择事件

function onSelectType(rec){
        //选中值
		if (rec=='2'){
            //普通发票对应税率
			pmsPlanList.pmsInvoiceTaxRate=pmsPlanList.pmsInvoiceTaxRateT
		}else {
            //专用发票对应税率
			pmsPlanList.pmsInvoiceTaxRate=pmsPlanList.pmsInvoiceTaxRateP
		}
		var row =$("#dgPmsPlanList").datagrid('getSelected');
		//获取行号
		var rowIndex = $("#dgPmsPlanList").datagrid('getRowIndex',row);
		var target = $('#dgPmsPlanList').datagrid('getEditor', {'index':rowIndex,'field':'taxRate'}).target;
		//清除原来的数据
		target.combobox('clear');
        //加载新下拉数据
		target.combobox('loadData',pmsPlanList.pmsInvoiceTaxRate);
	}

<table id="dgPmsPlanList"
		           data-options="
						fit: true,
						border: false,
						rownumbers: true,
						animate: true,
						collapsible: false,
						fitColumns: true,
						autoRowHeight: false,
						toolbar:'#toolbarPmsPlanList',
						idField :'id',
						singleSelect: true,
						checkOnSelect: true,
						selectOnCheck: false,
						pagination:false,
						onDblClickRow:onDbClickRowEvent,
						pageSize:dataOptions.pageSize,
						pageList:dataOptions.pageList,
						showFooter:true,
						striped:true">
		        <thead>
<tr>
<th  data-options="field:'pmsInvoiceType', halign:'center'" width="70" editor="{type:'combobox',options:{required:true,panelHeight:'auto',onSelect: onSelectType}}">
							<span style="color: red;">*span>发票类型
						th>
<th  data-options="field:'taxRate', halign:'center'" width="70" editor="{type:'combobox',options:{panelHeight:'auto',editable:false}}">
							<span style="color: red;">*span>税率
						th>
tr>