[Solved] ASP.Net GridView Cancel editing not working with DropDownList AutoPostBack

Hello,

I need your help.

On my Gridvew in C# ASP.NET I have

<asp:TemplateField ItemStyle-HorizontalAlign="Center">
    <ItemTemplate>
        <asp:ImageButton ID="btnedit" runat="server" CommandName="Edit"
            ImageUrl="edit_icon.gif" ToolTip= "Edit" />
    </ItemTemplate>
    <EditItemTemplate>
        <asp:ImageButton ID="btncancel" runat="server" CommandName="Cancel"
            ImageUrl="cancel.gif" ToolTip="Cancel editing" />
    </EditItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="BS"
    ItemStyle-HorizontalAlign="Justify">
    <ItemTemplate>
        <asp:Label ID="lbBS" runat="server" CssClass="ddl_Class_new"
            Text='<%# HttpUtility.HtmlDecode(MaP.SpliceText(Eval("BS").ToString(),11)) %>'>
        </asp:Label>
    </ItemTemplate> 
 <asp:TemplateField HeaderText="F" ItemStyle-CssClass="ddl_Class_new"
     ItemStyle-HorizontalAlign="Left">
     <ItemTemplate>
         <asp:Label ID="lblF" runat="server" Text='<%# Eval("F") %>'></asp:Label>
     </ItemTemplate>
     <EditItemTemplate>
         <asp:DropDownList ID="ddl" runat="server" CssClass="ddl_Class_new"
             AutoPostBack="true" BackColor="Yellow" OnSelectedIndexChanged="ddl">
         </asp:DropDownList>
     </EditItemTemplate>
 </asp:TemplateField>

I have problem when I try to cancel editing in the row, because if I have selected one value in DropDownList "ddl", e.g. "A" value instead of cancel editing it's opened the page "Default.aspx" and not cancel edit in GridView.

but if I delete AutoPostBack true, the Redirect don't working.

I have tried using without success

protected void gv_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
{
    gv.EditIndex = -1;
    DropDownList ddl = (DropDownList)FindControl("ddl");
    ddl.Items.Clear();
    DataBind;
}

protected void ddl(object sender, EventArgs e)
{
    DropDownList list = (DropDownList)sender;
    string value = (string)list.SelectedValue;
    switch (value)
    {
        case "A":
            Server.Transfer("Default.aspx");
            break;
        case "B":
            Server.Transfer("Default2.aspx");
            break;
    }
}

 Can you help me?