c#银行设计里面，更新不了数据库里面的内容，请高手支招帮忙解决一下

  private void button5_Click(object sender, EventArgs e)
        {
            int x = Convert.ToInt32(textBox1.Text.ToString());
            if (x > 3000 || x % 100 != 0)
            {
                groupBox2.ForeColor = Color.Red;
            }
            string lockID2;
            lockID2 = Form1.lockID;//lockID是在form1 里面的登录页面的登录帐号
            SqlConnection myConnection = new SqlConnection();
            myConnection.ConnectionString = "server=localhost;uid=sa;pwd=tdwind;database=bank";
            SqlCommand sqlCommand = new SqlCommand();
            sqlCommand.Connection = myConnection;
            sqlCommand.CommandType = CommandType.Text;
            sqlCommand.CommandText = "SELECT zhanghuyue FROM zhanghuxinxi WHERE zhanghao='" + lockID2 + "'";
            myConnection.Open();
            SqlDataReader dReader = sqlCommand.ExecuteReader(CommandBehavior.CloseConnection);
            string s = "";
            while (dReader.Read())
            {
                s += dReader["zhanghuyue"].ToString().Trim();
            }
            double zhye = Convert.ToDouble(s);
            string a=textBox1.Text;
            double qkje = Convert.ToDouble(a);
            if (qkje > zhye)
            {
                MessageBox.Show("您的余额不足");
            }
//到这上面一届执行都没有问题，下面这句要更改数据库的时候就死活改不了
            else
            {
                double yue = zhye - qkje;
                sqlCommand.CommandText = "update zhanghuxinxi set"+"zhanghuyue='"+yue+"'"+ "WHERE zhanghao='"+ lockID2 + "'";
                dReader.Close();
            }
        } c#代码修改银行设计更新不了数据库里面的值 --------------------编程问答-------------------- Update指令不能用sqlCommand.ExecuteReader
要用
sqlCommand.ExecuteNonQuery
--------------------编程问答-------------------- sql关键字都连起来了，加上空格。 --------------------编程问答-------------------- sqlCommand.CommandText = "update zhanghuxinxi set zhanghuyue='"+yue+"'"+ " WHERE zhanghao='"+ lockID2 + "'"; --------------------编程问答-------------------- sqlCommand.ExecuteReader --------------------编程问答--------------------



sqlCommand.CommandText = "update zhanghuxinxi set zhanghuyue='"+yue+"'"+ " WHERE zhanghao='"+ lockID2 + "'"; 

sqlCommand.ExecuteNonQuery();

补充：.NET技术 ,  C#