literal和eval不支持代码隐藏

Question

我试图通过从后面的代码获取eval来使视频路径在文字上工作。但我无法让它发挥作用。这是我到目前为止所做的：

On My Code Behind：

    public string GetVideoLink(string holdingval)
    {
        DataTable dt = new DataTable();
        holdingval = "";
        using (MySqlConnection con = new MySqlConnection(connectionstring))
        {
            con.Open();
            using (MySqlCommand com = new MySqlCommand("SELECT * FROM 
            discussion_table WHERE file_type='video' && 
            unique_id=@unique_id", con))
            {
                com.Parameters.AddWithValue("@unique_id", u.client_id);
                using (MySqlDataAdapter ad = new MySqlDataAdapter(com))
                {
                    dt.Clear();
                    ad.Fill(dt);
                    discussion_video_grid.DataSource = dt;
                    discussion_video_grid.DataBind();
                }
            }
        }

        foreach (DataRow rows in dt.Rows)
        {
            string locreader = rows.Field<string>("discussion_material_location");
            string locpath = "<video class=video_class Controls><Source src=" + locreader + " type=video/mp4></video>";
            holdingval = locpath;
        }

        return holdingval;
    }

在我的HTML上：

   <asp:Literal ID="videoshow" runat="server" Text='<%# 
   GetVideoLink(Eval(holdingval)) %> ' ></asp:Literal>