Get CommandArgument property value of ASP.Net ImageButton in C#

Hi there,

I need to retrieve some records if existing in a mysql database table and populate a gridview, which is initially populated with random data.

This is why I included this button on the web page, using CommandArgument

<asp:ImageButton ID="btnReco"
    ImageUrl="/aspnet/img/recovery_button.gif"
    runat="server"
    OnClick="btnReco_Click"
    CommandArgument="1"
    ToolTip="Indietro"
    CssClass="ddl_Class_new"
    Visible="true" />

And on the OnClick event this

protected void btnReco_Click(object sender, ImageClickEventArgs e)
{
    int t = Convert.ToInt32(MaP.Base64ForUrlDecode(Request.QueryString["t"].ToString()));
 
    switch (t)
    {
        case 1:
            gvProducts.DataSource = RetrieveProducts_reco();
            gvProducts.DataBind();
    }
}
 
private DataTable RetrieveProducts_reco()
{
    if (!String.IsNullOrEmpty(MaP.Container.TheObjectP))
    {
        DataTable dt = new DataTable();
        DataSet ds = new DataSet();
 
        using (MySqlConnection myConnectionString =
          new MySqlConnection(ConfigurationManager.ConnectionStrings["cn"].ConnectionString))
        {
            using (MySqlCommand cmd =
                new MySqlCommand("sp_20240311", myConnectionString))
            {
                cmd.CommandTimeout = 2147483;
                cmd.Connection.Open();
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.Clear();
 
                MySqlDataAdapter adapter =
                     new MySqlDataAdapter(cmd);
 
                if (!String.IsNullOrEmpty(Request.QueryString["ut"].ToString()))
                {
                    cmd.Parameters.AddWithValue("@spCCO",
                        MaP.Base64ForUrlDecode(Request.QueryString["ut"].ToString()));
                }
 
                adapter.Fill(ds);
 
                if (ds.Tables.Count > 0)
                {
                    dt = ds.Tables[0];
                    ....
 
                }
            }
        }
        return dt;
    }
    else
    {
        Page.ClientScript.RegisterStartupScript(this.GetType(), "Alert", "alert('KO');" +
            "window.location='http://..../';", true);
        return null;
    }
}

On this gridview there is a dropdownlist that should be populated when the recovery button is clicked with the value stored in database

I tried this solution without success because the value of the CommandArgument from recovery button is empty.

protected void gvProducts_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        string Ticket = e.Row.Cells[1].Text;
 
        ImageButton imgBtn = (ImageButton)e.Row.FindControl("btnReco");
        if (imgBtn != null)
        {
            string imgBtnReco = imgBtn.CommandArgument;
            Response.Write(imgBtnReco.ToString()); Response.End();
        }
    }
}

I'm not sure if this is the right approach, that's why I ask you for help in solving this problem, thanks