How to change the BackColor of Buttons inside a TableLayoutPanel?

Question

Is there any way to change the background color of Buttons inside a TableLayoutPanel?

The background color of the Buttons will be changed with a click of a Button outside of the TableLayoutPanel.
Actually I wanted to know how to identify Buttons which are inside a TableLayoutPanel.
I am providing a code block below. Please correct me.

private void button10_Click(object sender, EventArgs e)
{
    Button btnClicked = sender as Button;
       // wanted to convert the controls of tablelayoutpanel
    if (tableLayoutPanel1.Controls is Button)
    {
        btnClicked = (Button)tableLayoutPanel1.Controls;
    }
    else
        continue;
}

// Couldn't call the buttons inside the tablelayoutpanel.

Answer 1

Control.Controls is a collection. It cannot be cast to a single object. This:

tableLayoutPanel1.Controls is Button

will be notified in the code editor (green underline) with the message:

The given expression is never of the provided ('Button') type.

This cast will instead generate an error:

btnClicked = (Button)tableLayoutPanel1.Controls;

CS0030: Cannot convert type 'System.Windows.Forms.TableLayoutControlCollection' to 'System.Windows.Forms.Button'

---

To modify a property of all Button controls child of a TableLayoutPanel (or any other container), you can enumerate its Controls collection, considering only the child Controls of a specific Type.

For example, change to Color.Red the BackColor property of all Buttons inside a TableLayoutPanel:

foreach (Button button in tableLayoutPanel1.Controls.OfType<Button>()) {
    button.BackColor = Color.Red;
}

Change to Text property of all Buttons in the first Row:
Note that, here, I'm using a generic Control type instead of Button . This is because the Text property is common to all controls that derive from Control . The Text property is defined in the Control class.

foreach (Control ctl in tableLayoutPanel1.Controls.OfType<Button>())
{
    if (tlp1.GetRow(ctl) == 0)
        ctl.Text = "New Text";
}

Modify a property of a Control in the first Row, first Column of the TableLayoutPanel:
Here, I don't know what kind of control is located at coordinates (0, 0) , but I know it's an object derived from the Control class. So I can set a property that belongs to this class and is threfore inherited.
It may happen that a specific property is not relevant for a control Type. In this case nothing will happen (you can try to set the Text property of your TableLayoutPanel).

(tableLayoutPanel1.GetControlFromPosition(0, 0) as Control).BackColor = Color.Green;