ASP.NET

window.open(url, 'Download', 'height=1,width=1,top=0,left=-1000');

namespace immu.control
{
    [ToolboxData("<{0}:myControl runat=server></{0}:myControl>")]
    public class docControl : WebControl
    {

        public Button btn;

        protected override void CreateChildControls()
        {
            Panel pnl = new Panel();
            btn = new Button();
            btn.Text = "Click Me";
            btn.Click += new EventHandler(btn_Click);
            pnl.Controls.Add(btn);
            this.Controls.Add(pnl);
            //base.CreateChildControls();
        }

        public void btn_Click(object sender, EventArgs e)
        {
            HttpContext.Current.Response.Redirect("http://google.com");
        }
    }
}

<br />
                    <asp:TemplateField HeaderText="Image"><br />
                    <ItemTemplate><br />
                    <asp:Label ID="lblimage" runat="server" Text='<%# Eval("image") %>' /><br />
                    </ItemTemplate><br />
                    <EditItemTemplate><br />
                    <asp:Label ID="labelImage" runat="server" Text='<%# Eval("image") %>' /><br />
                    <asp:FileUpload ID="UpldImage" runat="server" /><br />
                    </EditItemTemplate><br />
                    </asp:TemplateField><br />

//To upload large image
FileUpload UpldImage = (FileUpload)DetailsView1.FindControl("UpldImage");
Label labelImage = (Label)DetailsView1.FindControl("labelImage");
string im = labelImage.Text;
if (UpldImage.HasFile)
{
    string fileName = "~/ProductImages/" + UpldImage.FileName;
    SqlDataSource2.UpdateParameters["image"].DefaultValue = fileName;
    UpldImage.SaveAs(Server.MapPath(fileName));
}
else
{
    SqlDataSource2.UpdateParameters["image"].DefaultValue = im;
    UpldImage.SaveAs(Server.MapPath(im));
}