Downloading files from a database table.

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VB

ASP.NET

Gridview

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Hi,

I have a GridView containing all the information and data related to a table, the 'content' table.

I would like to know how to download files by pressing the 'Download' button presented in the GridView.

GridView1 RowCommand Code:

Protected Sub GridView1_RowCommand(sender As Object, e As GridViewCommandEventArgs)
      If e.CommandName = "Download" Then

          Dim index As Integer = Convert.ToInt32(e.CommandArgument)
          Dim row As GridViewRow = GridView1.Rows(index)
          Dim contentID As Integer = Convert.ToInt32(GridView1.DataKeys(index).Value)


          Dim strQuery As String = "SELECT content_name, content_type, content_file FROM content where content_id=@id"

          Dim cmd As SqlCommand = New SqlCommand(strQuery)

          cmd.Parameters.AddWithValue("@id", contentID)

          Dim dt As DataTable = GetData(cmd)

          If dt IsNot Nothing Then

              download(dt)

          End If

      End If
  End Sub

GridView1 Code:

<asp:GridView ID="GridView1" runat="server" DataSourceID="SqlDataSource1" AllowSorting="True" AutoGenerateColumns="False" CellPadding="4" DataKeyNames="content_id" ForeColor="#333333" GridLines="None">
        <AlternatingRowStyle BackColor="White" ForeColor="#284775" />
        <Columns>
            <asp:CommandField ButtonType="Button" ShowDeleteButton="True" ShowSelectButton="True">
            <HeaderStyle HorizontalAlign="Center" VerticalAlign="Middle" />
            <ItemStyle BorderStyle="None" HorizontalAlign="Center" VerticalAlign="Middle" />

            </asp:CommandField>
            <asp:BoundField DataField="content_id" HeaderText="#" InsertVisible="False" ReadOnly="True" SortExpression="content_id">
            <HeaderStyle HorizontalAlign="Center" VerticalAlign="Middle" Width="30px" />
            <ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" Width="30px" />
            </asp:BoundField>
            <asp:BoundField DataField="content_name" HeaderText="Name" SortExpression="content_name">
            <HeaderStyle HorizontalAlign="Center" VerticalAlign="Middle" />
            <ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" />
            </asp:BoundField>
            <asp:BoundField DataField="content_type" HeaderText="Type" SortExpression="content_type">
            <HeaderStyle HorizontalAlign="Center" VerticalAlign="Middle" />
            </asp:BoundField>
            <asp:ButtonField ButtonType="Button" CommandName="Download" HeaderText="" Text="Download" />
        </Columns>
        <EditRowStyle BackColor="#999999" />
        <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
        <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
        <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
        <RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
        <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
        <SortedAscendingCellStyle BackColor="#E9E7E2" />
        <SortedAscendingHeaderStyle BackColor="#506C8C" />
        <SortedDescendingCellStyle BackColor="#FFFDF8" />
        <SortedDescendingHeaderStyle BackColor="#6F8DAE" />

    </asp:GridView>


SqlDataSource1 Code:

    <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:ConnStringDb1 %>" DeleteCommand="DELETE FROM [content] WHERE [content_id] = @content_id" InsertCommand="INSERT INTO [content] ([content_name], [content_type]) VALUES (@content_name, @content_type)" SelectCommand="SELECT [content_name], [content_type], [content_id] FROM [content]" UpdateCommand="UPDATE [content] SET [content_name] = @content_name, [content_type] = @content_type WHERE [content_id] = @content_id">
        <DeleteParameters>
            <asp:Parameter Name="content_id" Type="Int32" />
        </DeleteParameters>
        <InsertParameters>
            <asp:Parameter Name="content_name" Type="String" />
            <asp:Parameter Name="content_type" Type="String" />
        </InsertParameters>
        <UpdateParameters>
            <asp:Parameter Name="content_name" Type="String" />
            <asp:Parameter Name="content_type" Type="String" />
            <asp:Parameter Name="content_id" Type="Int32" />
        </UpdateParameters>
    </asp:SqlDataSource>

Full Code: http://pastebin.com/W4kdwfPn[^]

Whenever I click the 'Download' button, nothing happens.

Can anyone point me to the right direction?