再现EXT combobox 二级联动
由于项目的需要
在做二级联动的时候无法从数据库中读取内容，不知道是哪里的问题。各位谁帮忙给看看 O(∩_∩)O谢谢 先

//产品组下拉框var strGoupSelectBox=new Ext.form.ComboBox({typeAhead: true,triggerAction: 'all',lazyRender: true,transform:'prot_group',// -----------------------add by YDF at 2009-9-18 17:33:59hiddenName:"groupid",id:'goupSelectBox',name:'goupSelectBox',valueField:"keyid",      // 提交表单时，下拉框的值        displayField:'name',     // 显示在页面上下拉框的值emptyText:'请选择..',        editable:false,store: new Ext.data.JsonStore({          // 动态从后台提取数据并填充到 ComboBox            autoLoad:true,          url: '../data/sample_application_manager_getgroup_get_json.jsp?command=group',  mathod:'post',  fields: ['keyid', 'name']        }),listeners:{select:function(strGoupSelectBox,record,index){var groupValue = strGoupSelectBox.value;var sampleBox = document.getElementById("sampleCombox");alert(groupValue);if(groupValue==""){sampleBox.innerHTML="请先选择产品组";}}}});