想从Sql Server 中读出数据调试总是说 SqlDataReader reader= cmd1.ExecuteReader();' ' 附近有语法错误。不知道到底错在哪里?        private void button2_Click(object sender, EventArgs e)
        {
            string sqlstr3 = "select * from Table_2";
            SqlCommand cmd1 = new SqlCommand(sqlstr3, sqlConnection1);
            sqlConnection1.Open();
            SqlDataReader reader= cmd1.ExecuteReader();
            if (reader.Read() == true)
            {
                textBox1.Text = reader["学号"].ToString();
                textBox2.Text = reader["姓名"].ToString();
                textBox3.Text = reader["成绩"].ToString();
            }
            sqlConnection1.Close();
            reader.Close();