how to filter items from a selected dropdown list

Question

I am trying to filter items from a dropdownlist. I have written a select SQL statement in the XML table. Below is the respective codes. The name of my filter is TreatmentGroup .

The XML table with select statement code:

<predefined>
    <DetailFilters>
        <FilterInfo Name="CompanyID" DataType="xs:string" Kind="Session"/>
        <FilterInfo Name="BranchID" DataType="xs:string" Kind="Session"/>
        <FilterInfo Name="DepartmentID" DataType="xs:string" Kind="Session"/>
        <FilterInfo Name="MedicalSchemeID" DataType="xs:string" Kind="Form"/>
        <FilterInfo Name="TreatmentGroup" DataType="xs:string" Kind="Form"/>
    </DetailFilters>
    <DetailSelectStatement xsi:type="QLiteralExpr">
      SELECT
      TreatmentItems.TreatmentGroup As TreatmentGroup,
      MedicalSchemeDetail.*
      FROM
      MedicalSchemeDetail JOIN TreatmentItems ON
      MedicalSchemeDetail.CompanyID = TreatmentItems.CompanyID AND 
      MedicalSchemeDetail.BranchID = TreatmentItems.BranchID AND 
      MedicalSchemeDetail.DepartmentID = TreatmentItems.DepartmentID AND
      MedicalSchemeDetail.ItemID = TreatmentItems.TreatmentID 
      WHERE
      TreatmentGroup=@TreatmentGroup
      AND MedicalSchemeDetail.CompanyID = @CompanyID 
      AND MedicalSchemeDetail.BranchID = @BranchID 
      AND MedicalSchemeDetail.DepartmentID = @DepartmentID 
      AND MedicalSchemeDetail.MedicalSchemeID = @MedicalSchemeID 
      AND IsNull(MedicalSchemeDetail.Excluded,0) = 0
    </DetailSelectStatement>
<predefined>

This is the aspx code with the dropdown list:

<asp:Label runat="server" ID="label" SkinID="groupCaptionSkin" ForeColor="Navy" Font-Names="Tahoma" Font-Size="Small" Text="TreatmentGroup" />   
            <asp:DropDownList ID="ddlItemGroup" OnSelectedIndexChanged= "ddlPeriodStamp_SelectedIndexChanged" runat ="server" AutoPostBack = "True">
                <asp:ListItem Value="" Enabled="false"></asp:ListItem>
                <asp:ListItem Value="ALL">ALL</asp:ListItem>
                <asp:ListItem Value="Lab Test"> Lab Test</asp:ListItem>
                <asp:ListItem Value="RADIOLOGY TEST">RADIOLOGY</asp:ListItem>
                <asp:ListItem Value="NURSING">NURSING</asp:ListItem>
                <asp:ListItem Value="Prescription">Prescription</asp:ListItem>
                <asp:ListItem Value="VACCINES">VACCINES</asp:ListItem>
            </asp:DropDownList>
</asp:Label>

That´s the code behind with the filter:

protected void ddlPeriodStamp_SelectedIndexChanged(object sender, System.EventArgs e)
{       
    DropDownList ddlItemGroup = (DropDownList)sender;

    if (ddlItemGroup.SelectedValue != null)
        ApplyGridFilter();      
}

protected void ApplyGridFilter()
{      
    DBDataSource1.State.BusinessObject.DataPump.FormFilters.Clear();   
    DBDataSource1.State.BusinessObject.DataPump.FormFilters.Add("TreatmentGroup", TreatmentGroup);
    DBDataSource1.State.BusinessObject.Fill(null);
    MedicalSchemeDetailGrid.DataBind();
}

Answer 1

Your function ApplyGridFilter is called after the user selects an item in the list. I suggest you to bind the DropDownList from the code behind if you want to apply filters on the list you want to display, in PageLoad for example.