Webcontrol作为另一个Webcontrol的属性

Question

In asp.net sometimes a webcontrol needs to reference another webcontrol such as the gridview needs the id of the datasource object that it will bind to.

I have a property of my webcontrol that is a string (the id of the webcontrol I want to reference). How do I access the actual webcontrol based on this id?

Answer 1

this.FindControl()

http://msdn.microsoft.com/zh-CN/library/system.web.ui.control.findcontrol(v=VS.80).aspx

Answer 2

Here's a sample of a GridView bound to an ObjectDataSource, with the ObjectDataSource binding to a DropDownList for a parameter. This should get you started.

<asp:GridView ID="GridView1" runat="server" 
    AutoGenerateColumns="False" 
    DataSourceID="CustomerObjectDataSource" 
    DataKeyNames="CustomerID"
    AllowPaging="True" 
    AllowSorting="True" AutoGenerateDeleteButton="True" 
    AutoGenerateEditButton="True" AutoGenerateSelectButton="True" 
    onrowdeleted="GridView1_RowDeleted" onrowupdated="GridView1_RowUpdated">
    <Columns>
        ...
    </Columns>
</asp:GridView>

<asp:ObjectDataSource ID="CustomerObjectDataSource" runat="server" 
    EnablePaging="True" 
    MaximumRowsParameterName="totalRows" 
    StartRowIndexParameterName="firstRow" 
    TypeName="Northwind.Business.CustomerSource" 
    DataObjectTypeName="Northwind.Business.CustomerDTO"
    SelectMethod="Load" 
    UpdateMethod="Save" 
    InsertMethod="Insert" 
    DeleteMethod="Delete"
    SelectCountMethod="CustomerCount" 
    SortParameterName="sortExpression">
    <SelectParameters>
        <asp:ControlParameter ControlID="ddlRegion" Name="region" 
            PropertyName="SelectedValue" />
    </SelectParameters>
</asp:ObjectDataSource>