private void retrieveProductTypeCount_Click(object sender, EventArgs e) { SqlProductRepository products = new SqlProductRepository(connectionString); IReadOnlyList <ProductTypeCount> productList = products.RetrieveProductCount(); dataGridView1.DataSource = productList; for (int i = 0; i < dataGridView1.Columns.Count; i++) { DataGridViewColumn columnTwo = dataGridView1.Columns[1]; columnTwo.AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill; DataGridViewColumn columnThree = dataGridView1.Columns[2]; columnThree.AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill; } }