how change Aggregate Sum In Code Behind

[Peyman]

hi dear telerik team :
i have a RadGrid Like Below :

<telerik:RadGrid ID="grdUsers" runat="server" GridLines="None" Skin="Vista" DataSourceID="sdsUsers"
       AllowPaging="True" AutoGenerateColumns="False" OnItemCommand="grdUsers_ItemCommand"
       Width="900px" AllowSorting="True" PageSize="20">
       <MasterTableView AutoGenerateColumns="False" DataKeyNames="ID" DataSourceID="sdsUsers">
           <DetailTables>
               <telerik:GridTableView runat="server" DataKeyNames="ID,User_ID" DataSourceID="sdsDownload"
                   ShowFooter="True">
                   <ParentTableRelation>
                       <telerik:GridRelationFields DetailKeyField="User_ID" MasterKeyField="ID" />
                   </ParentTableRelation>
                   <CommandItemSettings ExportToPdfText="Export to Pdf" />
                   <RowIndicatorColumn FilterControlAltText="Filter RowIndicator column">
                       <HeaderStyle Width="20px" />
                   </RowIndicatorColumn>
                   <ExpandCollapseColumn FilterControlAltText="Filter ExpandColumn column">
                       <HeaderStyle Width="20px" />
                   </ExpandCollapseColumn>
                   <Columns>
                       <telerik:GridBoundColumn DataField="ID" DataType="System.Int32" FilterControlAltText="Filter ID column"
                           HeaderText="ID" ReadOnly="True" SortExpression="ID" UniqueName="ID">
                       </telerik:GridBoundColumn>
                       <telerik:GridBoundColumn DataField="User_ID" DataType="System.Int32" FilterControlAltText="Filter User_ID column"
                           HeaderText="User_ID" SortExpression="User_ID" UniqueName="User_ID">
                       </telerik:GridBoundColumn>

                       <telerik:GridBoundColumn DataField="FileSize" FilterControlAltText="Filter FileSize column"
                           HeaderText="FileSize" SortExpression="FileSize" UniqueName="FileSize" Aggregate="Sum">
                       </telerik:GridBoundColumn>
                   </Columns>
                   <EditFormSettings>
                       <EditColumn FilterControlAltText="Filter EditCommandColumn column">
                       </EditColumn>
                   </EditFormSettings>
               </telerik:GridTableView>
           </DetailTables>
           <CommandItemSettings ExportToPdfText="Export to Pdf"></CommandItemSettings>
           <RowIndicatorColumn FilterControlAltText="Filter RowIndicator column">
               <HeaderStyle Width="20px"></HeaderStyle>
           </RowIndicatorColumn>
           <ExpandCollapseColumn FilterControlAltText="Filter ExpandColumn column" Visible="True">
               <HeaderStyle Width="20px"></HeaderStyle>
           </ExpandCollapseColumn>
           <Columns>
               <telerik:GridBoundColumn DataField="ID" FilterControlAltText="Filter ID column" HeaderText="ID"
                   SortExpression="ID" UniqueName="ID">
                   <HeaderStyle HorizontalAlign="Center" VerticalAlign="Middle" />
                   <ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" />
               </telerik:GridBoundColumn>
               <telerik:GridBoundColumn DataField="FirstName" FilterControlAltText="Filter FirstName column"
                   HeaderText="FirstName" SortExpression="FirstName" UniqueName="FirstName">
                   <HeaderStyle HorizontalAlign="Center" VerticalAlign="Middle" />
                   <ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" />
               </telerik:GridBoundColumn>
           </Columns>
           <EditFormSettings>
               <EditColumn FilterControlAltText="Filter EditCommandColumn column">
               </EditColumn>
           </EditFormSettings>
       </MasterTableView>
       <FilterMenu EnableImageSprites="False">
       </FilterMenu>
       <HeaderContextMenu CssClass="GridContextMenu GridContextMenu_Default">
       </HeaderContextMenu>
   </telerik:RadGrid>

this is a Hierarchy grid with two tables (one master and one detail).
i have a column in detail table named (FileSize)!
FileSize Column Shows Us Some FileSizes In Bytes.
I want to have sum of FileSizes in The footer of FileSize column (in Detail table), so i set it's aggregate!
I wrote a method for change bytes to KB or MB or GB!
how can i change that Aggregate sum by my method in code behind for getting KB or MB or GB?

thanks in advance
best regards

[Peyman]

would be appreciate for some help ...

[Jayesh Goyani]

Hello,

protected void RadGrid1_PreRender(object sender, EventArgs e)
        {
            GridFooterItem Pfooter = (GridFooterItem)RadGrid1.MasterTableView.GetItems(GridItemType.Footer)[0];
            // Access Aggregate Value
            Response.Write("Footer from Parent : " + Pfooter["ID"].Text);


            foreach (GridDataItem item in RadGrid1.MasterTableView.Items)
            {
                if (item.HasChildItems)
                {
                    item.Expanded = true;
                    GridFooterItem cfooter = (GridFooterItem)item.ChildItem.NestedTableViews[0].GetItems(GridItemType.Footer)[0];
                    // Access Aggregate Value
                    Response.Write("Footer from child : " + cfooter["ID"].Text);
                }
            }

        }

<MasterTableView Name="ParentGrid"  >
                              <Columns>
                    <telerik:GridBoundColumn DataField="ID" HeaderText="ID" UniqueName="ID" Aggregate="Avg">
                    </telerik:GridBoundColumn></Columns>
                                       <DetailTables>
                    <telerik:GridTableView Name="ChildGrid">
                        <Columns>
                            <telerik:GridBoundColumn DataField="ID" HeaderText="ID" UniqueName="ID" Aggregate="Sum" >
                            </telerik:GridBoundColumn>
                                                </Columns>
                    </telerik:GridTableView>
                </DetailTables>
            </MasterTableView>

Thanks,
Jayesh Goyani