DevExpress ASPxComboBox 未過濾

Question

我有一個來自 DevExpress 套件的 ASPxComboBox，並且正在嘗試對其進行過濾。 如果我單擊組合框的下拉按鈕，它將顯示查詢的前幾個，就好像過濾器為空一樣。

如果我嘗試填充過濾器，或向下滾動以查看更多信息，它只會提供永久“加載”state。 存儲過程在使用適當的參數運行時返回正確的結果。 可能是什么問題呢？

編輯：我一直在 DevExpress 網站上關注本教程： http://demos.devexpress.com/ASPxEditorsDemos/ASPxComboBox/LargeDataSource.aspx

編輯（再次）：好的，如果我刪除該行：

<ClientSideEvents BeginCallback="function(s, e) { OnBeginCallback(); }" EndCallback="function(s, e) { OnEndCallback(); } " />

從組合框中，它將在cboInstructor_OnItemsRequestedByFilterCondition_SQL中遇到斷點，但是在轉到DataBind()時，它將拋出錯誤：

索引（從零開始）必須大於或等於零且小於參數列表的大小。

ASP文件

<form id="form1" runat="server">
<div>
    <dxe:ASPxComboBox ID="cboInstructor" runat="server" Width="100%"
        EnableCallbackMode="True" CallbackPageSize="10"
        IncrementalFilteringMode="Contains" ValueType="System.Int32" ValueField="employee_id"
        OnItemsRequestedByFilterCondition="cboInstructor_OnItemsRequestedByFilterCondition_SQL"
        OnItemRequestedByValue="cboInstructor_OnItemRequestedByValue_SQL" TextFormatString="{1} {2}"
        DropDownStyle="DropDown" DataSourceID="SqlDataSourceInstruct"
    >
        <Columns>
            <dxe:ListBoxColumn FieldName="display_forename" />
            <dxe:ListBoxColumn FieldName="display_surname" />
        </Columns>
        <ClientSideEvents BeginCallback="function(s, e) { OnBeginCallback(); }" EndCallback="function(s, e) { OnEndCallback(); } " />
    </dxe:ASPxComboBox>
    <asp:SqlDataSource ID="SqlDataSourceInstruct" runat="server" ConnectionString="Server=160.10.1.25;User ID=root;Password=password;Persist Security Info=True;Database=central" ProviderName="MySql.Data.MySqlClient" SelectCommand="GetUser" SelectCommandType="StoredProcedure">
        <SelectParameters>
            <asp:Parameter Name="filter" Type="String" />
            <asp:Parameter Name="startIndex" Type="Int32" />
            <asp:Parameter Name="endIndex" Type="Int32" />
        </SelectParameters>
    </asp:SqlDataSource>
</div>
</form>

CS文件

public partial class TestComboBox : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    protected void cboInstructor_OnItemsRequestedByFilterCondition_SQL(object source, ListEditItemsRequestedByFilterConditionEventArgs e)
    {
        ASPxComboBox comboBox = (ASPxComboBox)source;
        //SqlDataSourceInstruct.SelectCommand =
        //       @"SELECT CONCAT(display_Forename, ' ', display_Surname) FROM (SELECT employee_id, display_forename , display_surname, @rownum:=@rownum+1 AS rn FROM central.user_record, (SELECT @rownum:=0) AS r WHERE CONCAT(display_forename, ' ', display_surname) LIKE @filter ORDER BY display_surname ASC) AS st where st.rn between @startIndex and @endIndex";

        SqlDataSourceInstruct.SelectParameters.Clear();
        SqlDataSourceInstruct.SelectParameters.Add("filter", TypeCode.String, string.Format("%{0}%", e.Filter));
        SqlDataSourceInstruct.SelectParameters.Add("startIndex", TypeCode.Int64, (e.BeginIndex + 1).ToString());
        SqlDataSourceInstruct.SelectParameters.Add("endIndex", TypeCode.Int64, (e.EndIndex + 1).ToString());
        //comboBox.DataSource = SqlDataSourceInstruct;
        comboBox.DataBind();
    }

    protected void cboInstructor_OnItemRequestedByValue_SQL(object source, ListEditItemRequestedByValueEventArgs e)
    {
        long value = 0;
        if (e.Value == null)
            return;
        if (!Int64.TryParse(e.Value.ToString(), out value))
            return;
        ASPxComboBox comboBox = (ASPxComboBox)source;
        SqlDataSourceInstruct.SelectCommand = @"SELECT employee_id, display_surname, display_forename FROM central.user_record WHERE (employee_id = @ID) ORDER BY display_forename";

        SqlDataSourceInstruct.SelectParameters.Clear();
        SqlDataSourceInstruct.SelectParameters.Add("ID", TypeCode.Int64, e.Value.ToString());
        comboBox.DataSource = SqlDataSourceInstruct;
        comboBox.DataBind();

    }
}

MySQL 存儲過程

DELIMITER $$

USE `central`$$

DROP PROCEDURE IF EXISTS `GetUser`$$

CREATE DEFINER=`root`@`%` PROCEDURE `GetUser`(filter VARCHAR(50), startIndex INT, endIndex INT)
BEGIN
    SELECT employee_id, display_Forename, display_Surname
    FROM 
        (SELECT 
            employee_id
            , display_forename
            , display_surname
            , @rownum:=@rownum+1 AS rn  
        FROM central.user_record, 
            (SELECT @rownum:=0) AS r 
        WHERE CONCAT(display_forename, ' ', display_surname) LIKE filter
        ORDER BY display_surname ASC) AS st 
    WHERE st.rn BETWEEN startIndex AND endIndex;
    END$$

DELIMITER ;

Answer 1

為什么這些事情總是那么簡單？！ 我在ASPxComboBox中有TextFormatString="{1} {2}"並且只有 2 列，我之前有第三列但刪除了它並忘記更改TextFormatString我也剛剛刪除了ClientSideEvents ，因為它們來自我發布的示例上面，但我沒有使用它們。

現在一切正常！