Returns a DataGridView height to resize it correctly

GetDataGridViewHeight.cs

int GetDataGridViewHeight(DataGridView dataGridView)
{
    var sum = dataGridView.ColumnHeadersVisible ? dataGridView.ColumnHeadersHeight : 0 +
              dataGridView.Rows.OfType<DataGridViewRow>().Where(r => r.Visible).Sum(r => r.Height);

    return sum;
}