Ext对下拉列表value值的读取

var combox = new Ext.form.ComboBox({
	id:'likeName',
	store: comboxStore,
	displayField:'likeName',      //显示的值
	valueField:'likeType',          //提交的值
	hiddenName:'likeType',       //提交的值
	typeAhead: true,
	width:120,
	mode: 'local',                      //本地信息
	forceSelection: true,
	triggerAction: 'all',
	emptyText:'选择查询类型...',
	selectOnFocus:true
});
//读取
Ext.getCmp("likeName").getValue(); //读取到的是value值，而不是显示的值