Ext.NET组合框本地查询未返回数据时的回调

Question

使用Ext.NET组合框。

<ext:ComboBox runat="server" 
ID="ComboBoxCategorizedList" 
QueryMode="Local" 
ValueField="Id" 
EmptyText="Type to begin search..." 
TypeAhead="false"
DisplayField="Name"
Width="500"
NoteAlign="Down" EnableKeyEvents="true"   
Note="Press 'Search' icon or Press ENTER for more results"
RemoveClearTrigger="true">
<%--Note="Type '*' for a full list"--%>
<HtmlBin>
<ext:XScript runat="server">
<script type="text/javascript">
$(window).on("__refresh__", function () {
#{ StoreComboBoxCategorizedList }.reload();
});
</script>
</ext:XScript>
</HtmlBin>  
<Store>
<ext:Store runat="server" ID="StoreComboBoxCategorizedList" OnReadData="ComboBoxCategorizedList_ReadData">
<Proxy>
<ext:PageProxy />
</Proxy>
<Model>
<ext:Model Id="ModelCategorizedComboBox" runat="server" IDProperty="Id">
<Fields>
<ext:ModelField Name="Id" />
<ext:ModelField Name="Name" />
<ext:ModelField Name="Type"  />
<ext:ModelField Name="RefId"  />
<ext:ModelField Name="Description"  />
</Fields>
</ext:Model>
</Model>
<Listeners>
<Update Handler="#{ComboBoxCategorizedList}.expand();" />
<EndUpdate Handler="categorizedList();" />
</Listeners>
<Parameters>
<ext:StoreParameter Mode="Raw" Name="filter" Value="#{ComboBoxCategorizedList}.getValue()" />
</Parameters>
</ext:Store>
</Store>
<Triggers>
<ext:FieldTrigger Icon="Clear"/>
<ext:FieldTrigger Icon="Search"></ext:FieldTrigger>
</Triggers>
<Listeners>
<SpecialKey Fn="enterKeyPressHandler" />
<Expand Handler="categorizedList();" Delay="100" />
<BeforeSelect Fn="onBeforeSelect" />
<KeyPress  Handler="#{ComboBoxCategorizedList}.getTrigger(1).onClick();" Buffer="1000" />
<Change Handler="filterComboxBoxFunction(#{StoreComboBoxCategorizedList}, #{ComboBoxCategorizedList}.getValue()); #{ComboBoxCategorizedList}.expand(); categorizedList();" Delay="100" />
</Listeners>

不是要求调试帮助，但我想知道Ext.NET或Extjs开发人员是否有通用的解决方案：非常简单。。。我只想在本地搜索未返回任何记录时启动远程搜索。所以我正在寻找最好的方式把这个连接到combobox。我已经考虑过使用Expand事件和BeforeQuery事件，但这似乎不够。

我正在寻找最佳实践，这样我就可以添加一个"；OnLocalQuery"；事件到我的组合框；然后在本地查询返回0个匹配项的情况下采取行动。

Answer 1

我使用这个函数，它工作得很好。。并且在没有QueryMode＝"的情况下；"本地"：

<ext:ComboBox ID="cmb_name" runat="server" FieldLabel="ComboBox" EmptyText="-Select-" HideTrigger="true" TriggerAction="All" SelectOnFocus="true" DisplayField="Name" ValueField="Id" Editable="true" TabIndex="11">
<Store>
<ext:Store ID="str_ComboBox" runat="server" PageSize="10">
<Model>
<ext:Model ID="mdl_ComboBox" runat="server">
<Fields>
<ext:ModelField Name="Id" />
<ext:ModelField Name="Name" />
<ext:ModelField Name="Type"  />
<ext:ModelField Name="RefId"  />
<ext:ModelField Name="Description"  />
</Fields>
</ext:Model>
</Model>
</ext:Store>
</Store>
<Listeners>
<Change Fn="fn_filter" />
</Listeners>
</ext:ComboBox>
<script type="text/javascript">
var fn_filter = function (_this, newValue, oldValue, eOpts) {
var n = 0;
if (_this.lastQuery == undefined || _this.lastQuery == null) {
_this.lastQuery = "";
}
_this.getStore().clearFilter(true);
_this.getStore().load();
_this.store.filter(function (item) {
if (item.get('Name').includes(_this.getRawValue())) {
n = n + 1;
return true;
}
else {
return false;
}
});
_this.expand();
if (n == 0) {
//returns no records
//enter code here Callback
}
}
</script>