EXTJS 初始化Combobox的数据

combobox获取数据有两种方式：即参数mode的取值，local或者remote
我比较喜欢的数据格式是JSON，采用Ext.data.SimpleStore
1、mode:'local'
var departmentCode = [
   ['1','研发部'],['2','人事处'],['3','总经办']
];

new Ext.form.ComboBox({
    fieldLabel: 'Department Code',
    name:'departmentCode',
    forceSelection: true,
    listWidth: 200,
    store: new Ext.data.SimpleStore(...{
           fields: ['value', 'text'],
           data : departmentCode
    }),
    valueField:'value',
    displayField:'text',
    typeAhead: true,
    mode: 'local',
    triggerAction: 'all',
    selectOnFocus:true,
    allowBlank:false
})

2、mode:'remote'
var combo = new Ext.data.JsonStore({
     url:'url',
     fields: ['departmentId','departmentname']});

combo.load();

new Ext.form.ComboBox({
      fieldLabel: 'Department',
      name:'department',
      forceSelection: true,
      listWidth: 150,
      store: combo,
      valueField:'departmentId',
      displayField:'departmentname',
      typeAhead: true,
      mode: 'local',
      triggerAction: 'all',
      selectOnFocus:true,
      allowBlank:false
})
其中json的格式如：{['1','研发部'],['2','财务处']}

注意：如果返回的json数据有多列,需要在new Ext.data.JsonStore的时候,在fields一项中填写所有column的名字,否则不能填充combobox