标签信息无法访问

Question

我有一个WinForms程序，该程序在启动时设置了TableLayoutPanel。我向其中添加了另一组TLP，并设置了一个标签，该标签与我要绘制的颜色相对应：

private void Set_IO_Display()
{   
// this sets up the TLP at run time. this all works fine. The TLPs set up here are referred to in `Update_GUI_Inputs()`

                string Type; // these are all defined from an XML file
                string Device = "ED527"; //these are examples
                string Line = "1";//example
                string label = "Test"; //example
                string Colour = "Green"; //example

                TableLayoutPanel IOTable = new TableLayoutPanel();
                IOTable.ColumnCount = 6;
                IOTable.RowCount = 1;
                IOTable.Name = Device + "_" + Line;
                #region AddLabels
                IOTable.Controls.Add(new Label
                {
                    Text = label,
                    TextAlign = ContentAlignment.MiddleCenter,
                    BorderStyle = BorderStyle.FixedSingle,
                    BackColor = Color.White,
                    Dock = DockStyle.Fill
                }); // I add another 5 labels here

                    IOTable.Dock = DockStyle.Fill;
                    IOTable.Tag = Colour; 
}

private void UpdateGUI_Inputs()
{
//this is this sub for the updates, which works okay 
                    string I_Card_Name = "ED527_" + i.ToString();
                    TLP = TLP_IO_Info.Controls.Find(I_Card_Name, true).FirstOrDefault() as TableLayoutPanel;// <-- this works fine - the name given in Set_IO_Display() is found and I can do something with it.
                    lbl = TLP.GetControlFromPosition(4, 0) as Label;// <<-- this also works fine.
                    lbl.Invoke((MethodInvoker)delegate { lbl.BackColor = Color.FromName(TLP.Tag); }); //<-- the TLP tag is returned as null - Why?
}

即使找到了TableLayoutPanel及其子标签，并且我可以对它们进行处理，但调用时它不会返回该标签。

如何获取标签？