Extjs中ComboBox二级联动操作例子

本例子使用Extjs .NET版本，Coolite.Ext.Web控件，下面开始以实例操作：

首先建立test.aspx页面，加载控件

<%@ Register assembly="Coolite.Ext.Web" namespace="Coolite.Ext.Web" tagprefix="ext" %>

主要代码：

    <form id="form1" runat="server">
    <div>
    <ext:ScriptManager ID="ScriptManager1" runat="server" />
        <ext:Store runat="server" ID="ClassStore" > <!-- 一级数据源 -->
          <Reader>
             <ext:JsonReader ReaderID="class_id">
                    <Fields>
                       <ext:RecordField Name="class_id" Type="String" />
                       <ext:RecordField Name="class_name" Type="String" />
                   </Fields>
               </ext:JsonReader>
         </Reader>
        </ext:Store>
        <ext:Store runat="server" ID="TypeStore" > <!-- 动态二级数据源 -->
          <Reader>
             <ext:JsonReader ReaderID="type_id">
                    <Fields>
                       <ext:RecordField Name="type_id" Type="String" />
                       <ext:RecordField Name="type_name" Type="String" />
                   </Fields>
               </ext:JsonReader>
         </Reader>
         <Listeners>
            <Load Handler="#{type_ComboBox}.setValue(#{type_ComboBox}.store.getAt(0).get('type_id'));" />
         </Listeners>
        </ext:Store> <!------ 以下为数据展现 -->

   <table cellpadding="0" cellspacing="0">
  <tr>
   <td>
     <ext:ComboBox ID="class_box" runat="server"
      DisplayField="class_name"
      ValueField="class_id"
      Editable="false"
      TypeAhead="true"
      TriggerAction="All"
      SelectOnFocus="true"
      Mode="Local"
      ForceSelection="true"
      StoreID="ClassStore"
      Width="110px"
      >
     <Listeners>
    <Select Handler="Coolite.AjaxMethods.Resource_SelectedIndexChanged();" />
     </Listeners>
     </ext:ComboBox>
   </td>
   <td>
      <ext:ComboBox ID="type_ComboBox" runat="server"
       DisplayField="type_name"
       ValueField="type_id"
       Editable="false"
       TypeAhead="true"
       TriggerAction="All"
       SelectOnFocus="true"
       Mode="Local"
       ForceSelection="true"
       StoreID="TypeStore"
       Width="110px"
      >
      </ext:ComboBox>                                    
   </td>
  </tr>
   </table>

下面是后台.cs主要代码：