ext.net中ComboBox空间实现模糊查询

<ext:ComboBox ID="ComboBox1" runat="server" DisplayField="MingCheng" ValueField="Id" StoreID="Employ" Width="100">
                                    <Listeners>
                                        <BeforeQuery Fn="bq" />
                                    </Listeners>
                                </ext:ComboBox>

var bq = function (e) {
            var combo = e.combo;
            if (!e.forceAll) {
                var input = e.query;
                // 检索的正则
                var regExp = new RegExp(".*" + input + ".*");
                // 执行检索
                combo.store.filterBy(function (record, id) {
                    // 得到每个record的项目名称值
                    var text = record.get(combo.displayField);
                    return regExp.test(text);
                });
                combo.expand();
                return false;
            }
        }