C# 简单连接数据库并执行SQL查询语句

private void button1_Click(object sender, EventArgs e)
{
SqlConnection conn = new SqlConnection();
conn.ConnectionString = "Data Source=.;Password=123456;User ID=sa;Initial Catalog=guo;database=guo";
conn.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
cmd.CommandText = "select * from dbo.[user]";
SqlDataReader reader = cmd.ExecuteReader();

while (reader.Read())
{
Object[] values = new Object[reader.FieldCount];
int nCount = reader.GetValues(values);
for (int i = 0; i != nCount; ++i)
listBox1.Items.Add(values[i]);
}
//             while (reader.Read())
//             {
//                     listBox1.Items.Add(reader[1]);
//             }
conn.Close();
}