C# how I add checkbox in header of gridview

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WinForms

C#3.5

C#5.0

C#6.0

i'v datagridview and i'v created column checkbox for select and here my code it's work fine

private void addchkbox()
        {
            DataGridViewCheckBoxColumn col = new DataGridViewCheckBoxColumn();
            dataGridView6.Columns.Insert(4, col);
        }

how can i make also checkbox for my header of datagridview for check/uncheck all

What I have tried:

i'm trying to used header methods but all give me error