You need to consider the offset of the monitor before setting the position, but other than that, it should be pretty simple.
if (center) { form.Location = new Point ( biggestScreen.WorkingArea.X + ((biggestScreen.WorkingArea.Width + form.Width)/2), biggestScreen.WorkingArea.Y + ((biggestScreen.WorkingArea.Height + form.Height)/2) ); }
But Form.CenterToScreen () should work fine, but apparently Microsoft doesn't recommend using it? I do not know why.
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