column count property cannot be set on a databound c#

Question

column count property cannot be set on a databound datagridview control c#

 

dataGridView1.ColumnCount = 7;

dataGridView1.Columns[0].HeaderText = "Product_ID";

dataGridView1.Columns[0].DataPropertyName = "Product_ID";

dataGridView1.Columns[0].Visible = false;

dataGridView1.Columns[1].HeaderText = "Name";

dataGridView1.Columns[1].DataPropertyName = "prodName";

dataGridView1.Columns[2].HeaderText = "Description";

dataGridView1.Columns[2].DataPropertyName = "_desc";

dataGridView1.Columns[3].HeaderText = "Tax_ID";

dataGridView1.Columns[3].DataPropertyName = "Tax_ID";

dataGridView1.Columns[3].Visible = false;

dataGridView1.Columns[4].HeaderText = "Unit_ID";

dataGridView1.Columns[4].DataPropertyName = "Unit_ID";

dataGridView1.Columns[4].Visible = false;

dataGridView1.Columns[5].HeaderText = "Tax";

dataGridView1.Columns[5].DataPropertyName = "Tax";

dataGridView1.Columns[6].HeaderText = "Unit";

dataGridView1.Columns[6].DataPropertyName = "UnitName"; dataGridView1.DataSource = dt;

}