DAL数据库学习（2）

通过数据库连接有很多好处。虽然对于现在的各种存储结构了解不多，但是凭我现在的认知来看，数据库是现在乃至未来的“潮流”，完全引领着数据存储的走向。

我在原来所做测试的基础上按照网上及书上的方法进行了新的测试（在窗口模式下），代码如下

 private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            comboBox1.Text = "项目组员";
            string strConnection = "Provider=Microsoft.ACE.OLEDB.12.0;";
            strConnection += @"Data Source=Database.accdb";
            OleDbConnection objConnection = new OleDbConnection(strConnection);
            objConnection.Open();
            string a = listBox1.SelectedValue.ToString();
            OleDbCommand cmm = new OleDbCommand("select * from 项目组员 where User ='" + a + "'", objConnection);
            OleDbDataReader coo = cmm.ExecuteReader();
            while (coo.Read())
            {
                textBox1.Text = coo["Code"].ToString();
                textBox2.Text = coo["Realname"].ToString();
                textBox3.Text = coo["Birthday"].ToString();
                textBox4.Text = coo["Joindate"].ToString();
                textBox5.Text = "";
                textBox6.Text = coo["Grade"].ToString();
                textBox7.Text = coo["User"].ToString();
            }
            coo.Close();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string strConnection = "Provider=Microsoft.ACE.OLEDB.12.0;";
            strConnection += @"Data Source=Database.accdb";
            OleDbConnection objConnection = new OleDbConnection(strConnection);
            objConnection.Open();
            if (textBox5.Text == textBox1.Text)
            {
                OleDbCommand comm = new OleDbCommand("update "+comboBox1.Text+" set Code='" + textBox1.Text + "' where User='" + textBox7.Text + "'", objConnection);
                comm.ExecuteReader();
                comm = new OleDbCommand("update  项目信息 set Realname='" + textBox2.Text + "'where User='" + textBox7.Text + "'", objConnection);
                comm.ExecuteReader();
                comm = new OleDbCommand("update  " + comboBox1.Text + " set Birthday='" + textBox3.Text + "'where User='" + textBox7.Text + "'", objConnection);
                comm.ExecuteReader();
                comm = new OleDbCommand("update " + comboBox1.Text + " set Joindate='" + textBox4.Text + "' where User='" + textBox7.Text + "'", objConnection);
                comm.ExecuteReader();
                comm = new OleDbCommand("update " + comboBox1.Text + " set Grade='" + textBox6.Text + "' where User='" + textBox7.Text + "'", objConnection);
                comm.ExecuteReader();
                MessageBox.Show("保存成功!");
                objConnection.Close();
            }
            else
            {
                MessageBox.Show("确认密码错误，请再次输入!");
            }
            objConnection.Close();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            comboBox1.Text = "项目管理员";
            string strConnection = "Provider=Microsoft.ACE.OLEDB.12.0;";
            strConnection += @"Data Source=Database.accdb";
            OleDbConnection objConnection = new OleDbConnection(strConnection);
            objConnection.Open();
            OleDbCommand cmm = new OleDbCommand("select * from 项目管理员 ", objConnection);
            OleDbDataReader coo = cmm.ExecuteReader();
            while (coo.Read())
            {
                textBox1.Text = coo["Code"].ToString();
                textBox2.Text = coo["Realname"].ToString();
                textBox3.Text = coo["Birthday"].ToString();
                textBox4.Text = coo["Joindate"].ToString();
                textBox5.Text = "";
                textBox6.Text = coo["Grade"].ToString();
                textBox7.Text = coo["User"].ToString();
            }
            coo.Close();
        }

        private void button3_Click(object sender, EventArgs e)
        {
            comboBox1.Text = "总经理";
            string strConnection = "Provider=Microsoft.ACE.OLEDB.12.0;";
            strConnection += @"Data Source=Database.accdb";
            OleDbConnection objConnection = new OleDbConnection(strConnection);
            objConnection.Open();
            OleDbCommand cmm = new OleDbCommand("select * from 总经理 ", objConnection);
            OleDbDataReader coo = cmm.ExecuteReader();
            while (coo.Read())
            {
                textBox1.Text = coo["Code"].ToString();
                textBox2.Text = coo["Realname"].ToString();
                textBox3.Text = coo["Birthday"].ToString();
                textBox4.Text = coo["Joindate"].ToString();
                textBox5.Text = "";
                textBox6.Text = coo["Grade"].ToString();
                textBox7.Text = coo["User"].ToString();
            }
            coo.Close();
        }

UI界面如图：

通过与数据库的连接   就可以实现用户信息的修改了。

明天将开始对网站添加数据库测试量。