Buyur hocam
SqlConnection con = new SqlConnection(" server= EE\\SQLEXPRESS; initial catalog = bankamatikotomasyonu; integrated security = sspi ");
private void button1_Click(object sender, EventArgs e)
{
SqlCommand komut = new SqlCommand("selecet * from musteriler where ID= @p1 or tcNo= @p2 ", con);
komut.Parameters.AddWithValue("@p1", txtAra.Text);
komut.Parameters.AddWithValue("@p2", txtAra.Text);