Question

I am using a tableLayoutPanel which consist of two rows. In first row I want two columns,
and in second row I only need one column. How can I do this?

Answer 1

With the designer: put a control in the 2nd row and set its ColumnSpan property to 2.

In code:

    public Form1() {
        InitializeComponent();
        var button = new Button();
        button.Dock = DockStyle.Fill;
        tableLayoutPanel1.Controls.Add(button);
        tableLayoutPanel1.SetCellPosition(button, new TableLayoutPanelCellPosition(0, 1));
        tableLayoutPanel1.SetColumnSpan(button, 2);
    }