java swing開發學生成績管理系統

臨近期末，java實驗報告，真的是很手忙腳亂，看了那麼多篇，沒有一篇說的比較完整的，那這篇的話就整體的說一下吧，
這個是用swing開發的學生 成績 管理系統，其中與數據庫建立連接，數據庫用的是SQL server 2012，java開發環境需要用到eclipise
因爲個人知識儲備的不足，因此代碼中有部分功能不能全部實現，本篇的源碼來源於GitHub，感謝網友分享。
本題的源代碼如下

package practice_student;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.*;
import java.util.Arrays;
import java.util.List;
import java.util.Vector;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Student_Mangement extends JFrame {//程序入口
    private JPanel panel_1 = new JPanel();
    private JButton btnConfim = new JButton("登陸");
    private JButton btnSignUp = new JButton("註冊");
    private JTextField userName = new JTextField(20);
    private JPasswordField pass = new JPasswordField(20);
    private JLabel userLaber = new JLabel("用戶名");
    private  JLabel passLaber = new JLabel("密碼");
     JLabel text = new JLabel("歡迎使用學生成績管理系統！");
    private ConnetDB conn = new ConnetDB();
    private ImageIcon icon=new ImageIcon("D:/icon.jpg");
    public static void main(String[] args) {
        Student_Mangement enterGui=new Student_Mangement();
     }
     public Student_Mangement(){
         super();
         this.setIconImage(icon.getImage());
         this.setTitle("學生成績管理系統");
         this.setBounds(650, 250, 500, 400);
         this.setVisible(true);
         this.setResizable(false);
         this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         this.setLayout(null);
         panel_1.setLayout(null);
         panel_1.setBounds(0, 50, 600, 250);
         text.setBounds(140, 0, 250, 50);
         btnConfim.setBounds(150, 130, 70, 30);
         btnSignUp.setBounds(250,130,70,30);
         userLaber.setBounds(95, 50, 40, 30);
         passLaber.setBounds(95, 80, 40, 30);
         userName.setBounds(135, 50, 200, 30);
         pass.setBounds(135, 80, 200, 30);
         panel_1.add(text);
         panel_1.add(userLaber);
         panel_1.add(userName);
         panel_1.add(passLaber);
         panel_1.add(pass);
         panel_1.add(btnConfim);
         panel_1.add(btnSignUp);
         this.add(panel_1);
         setActionLintener();
    }
       private void setActionLintener(){
        btnConfim.addActionListener(new ActionListener() {
            //內部類實現主界面
            class MainGUI extends JFrame{
                final int COLUMN=10;
                private final List<String> TITLE= Arrays.asList("姓名","學號","教師","院系","英語成績","高數成績",
                        "大物成績","平均分","最高分","最低分");
                Vector<Vector<String>> dataModel=new Vector<>();
                private JMenuBar bar=new JMenuBar();
                private JMenu menu_stu =new JMenu("管理學生成績");
                private JMenu menu_course =new JMenu("課程成績排名");
                private JMenu menu_exUser =new JMenu("退出登陸");
                private JMenuItem showAll =new JMenuItem("顯示所有學生成績");
                private JMenuItem addStu =new JMenuItem("添加學生");
                private JMenuItem findByName =new JMenuItem("按關鍵字查詢");
                private JMenuItem showEng =new JMenuItem("按英語成績排名");
                private JMenuItem showMath =new JMenuItem("按高數成績排名");
                private JMenuItem showPhy =new JMenuItem("按大物成績排名");
                private JMenuItem userEx =new JMenuItem("退出登錄");
                private JButton btnDelete =new JButton("刪除此條");
                private JButton btnChange =new JButton("修改此條");
                private JTable table;
                private ConnetDB conn=new ConnetDB();
                public MainGUI(){
                    super();
                    this.setTitle("學生成績管理系統");
                    this.setBounds(650,250,800,500);
                    this.setVisible(true);
                    this.setResizable(false);
                    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    this.setIconImage(icon.getImage());
                    //菜單欄
                    menu_stu.add(showAll);
                    menu_stu.add(addStu);
                    menu_stu.add(findByName);
                    menu_course.add(showEng);
                    menu_course.add(showMath);
                    menu_course.add(showPhy);
                    menu_exUser.add(userEx);
                    bar.add(menu_stu);
                    bar.add(menu_course);
                    bar.add(menu_exUser);
                    this.setJMenuBar(bar);

                    Vector<String> titles=new Vector<>(TITLE);
                    table=new JTable(dataModel,titles);
                    table.getTableHeader().setReorderingAllowed(false);//表頭不可拖動
                    for (int i = 0; i < COLUMN; i++) {
                        if(1==i||i==3){//這2列數據更長一些
                            table.getColumnModel().getColumn(i).setPreferredWidth(150);
                        }
                    }
                    //承載table的panel
                    JPanel tablePanel=new JPanel();
                    tablePanel.setLayout(new BoxLayout(tablePanel,BoxLayout.Y_AXIS));
                    this.add(tablePanel);
                    JScrollPane jScrollPane=new JScrollPane();
                    jScrollPane.setViewportView(table);
                    tablePanel.add(jScrollPane, BorderLayout.CENTER);
                    tablePanel.add(btnChange);
                    tablePanel.add(btnDelete);
                    tablePanel.updateUI();
                    setActionListener();
                }
                //監聽事件
                private void setActionListener(){
                    btnChange.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            int row = table.getSelectedRow();
                            int column = table.getSelectedColumn();
                            if (row == -1 || column == 0) return;
                            String val = dataModel.get(row).get(column);
                            String name = dataModel.get(row).get(0);
                            //解決表列名和table列名不一樣
                            String convert="";
                            if(TITLE.get(column).equals("學號")) {
                                convert = "number";
                            }else if (TITLE.get(column).equals("教師")) {
                                convert = "teacher";
                            }else if (TITLE.get(column).equals("院系")) {
                                convert = "major";
                            }else if (TITLE.get(column).equals("英語成績")) {
                                convert = "english";
                            }else if (TITLE.get(column).equals("高數成績")) {
                                convert = "math";
                            }else if (TITLE.get(column).equals("大物成績")) {
                                convert = "physic";
                            }
                            String sql = "update Student set " + convert + " = ? where Sname = '"+name+"';";
                            PreparedStatement ps;
                            try {
                                ps = conn.getConnect().prepareStatement(sql);
                                if (TITLE.get(column).equals("學號")||TITLE.get(column).equals("英語成績")||
                                        TITLE.get(column).equals("高數成績")||
                                TITLE.get(column).equals("大物成績")) {
                                    ps.setInt(1, Integer.parseInt(val));
                                }
                                else {
                                    ps.setString(1, val);
                                }
                                ps.executeUpdate();
                            } catch (SQLException e1) {
                                e1.printStackTrace();
                            }
                            table.validate();
                            table.updateUI();
                        }
                    });
                    btnDelete.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            int row = table.getSelectedRow();
                            String sname = dataModel.get(row).get(0);
                            String sql = "delete from Student where Sname = '" + sname + "';";
                            try {
                                if (conn.getConnect().createStatement().executeUpdate(sql) == 0) return;
                                dataModel.remove(row);
                                //更新表格
                                table.validate();
                                table.updateUI();
                            } catch (SQLException e1) {
                                e1.printStackTrace();
                            }
                        }
                    });
                    showAll.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            dataModel.clear();
                           Statement stmt;
                            try {
                                stmt =conn.getConnect().createStatement();
                                ResultSet rs = stmt.executeQuery("select *from Student");
                                initTable(rs);
                            } catch (SQLException e1) {
                                e1.printStackTrace();
                            }
                            //更新表格
                            table.validate();
                            table.updateUI();
                        }
                    });
                    addStu.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            class AddStu extends JFrame {
                                ConnetDB conn = new ConnetDB();
                                private JTextField txName=new JTextField();
                                private JTextField txNo=new JTextField();
                                private JTextField txTeacher=new JTextField();
                                private JTextField txCol=new JTextField();
                                private JTextField txEng=new JTextField();
                                private JTextField txMath=new JTextField();
                                private JTextField txPhy=new JTextField();
                                private JButton btnComfirm=new JButton("確認");
                                private JPanel panel=new JPanel();
                                private JLabel lbName =new JLabel("姓名");
                                private JLabel lbNo =new JLabel("學號");
                                private JLabel lbTeacher =new JLabel("教師");
                                private JLabel lbCol =new JLabel("院系");
                                private JLabel lbEng =new JLabel("英語成績");
                                private JLabel lbMath =new JLabel("高數成績");
                                private JLabel lbPhy =new JLabel("大物成績");

                                public AddStu(){
                                    super();
                                    this.setTitle("輸入學生信息");
                                    this.setBounds(820, 330, 350, 300);
                                    this.setVisible(true);
                                    this.setResizable(false);
                                    this.setIconImage(icon.getImage());
                                    panel.setLayout(null);
                                    txName.setBounds(70,5,200,30);
                                    txNo.setBounds(70,35,200,30);
                                    txTeacher.setBounds(70,65,200,30);
                                    txCol.setBounds(70,95,200,30);
                                    txEng.setBounds(70,125,200,30);
                                    txMath.setBounds(70,155,200,30);
                                    txPhy.setBounds(70,185,200,30);
                                    btnComfirm.setBounds(130,220,70,30);

                                    lbName.setBounds(30,5,200,30);
                                    lbNo.setBounds(30,35,200,30);
                                    lbTeacher.setBounds(30,65,200,30);
                                    lbCol.setBounds(30,95,200,30);
                                    lbEng.setBounds(20,125,200,30);
                                    lbMath.setBounds(20,155,200,30);
                                    lbPhy.setBounds(20,185,200,30);
                                    panel.add(lbName);
                                    panel.add(txName);
                                    panel.add(lbNo);
                                    panel.add(txNo);
                                    panel.add(lbTeacher);
                                    panel.add(txTeacher);
                                    panel.add(lbCol);
                                    panel.add(txCol);
                                    panel.add(lbEng);
                                    panel.add(txEng);
                                    panel.add(lbMath);
                                    panel.add(txMath);
                                    panel.add(lbPhy);
                                    panel.add(txPhy);
                                    panel.add(btnComfirm);
                                    this.add(panel);
                                    btnComfirm.addActionListener(new ActionListener() {
                                        @Override
                                        public void actionPerformed(ActionEvent e) {
                                            String sname="";
                                            int sNo=Integer.parseInt(txNo.getText());
                                            String tname="";
                                            String col="";
                                            int eng=Integer.parseInt(txEng.getText());
                                            int math=Integer.parseInt(txMath.getText());
                                            int phy=Integer.parseInt(txPhy.getText());
                                            if (!("".equals(txName.getText()))){
                                                sname=txName.getText();
                                            }
                                            if (!("".equals(txTeacher.getText()))){
                                                tname=txTeacher.getText();
                                            } if (!("".equals(txCol.getText()))){
                                                col=txCol.getText();
                                            }
                                            String sql="insert into Student(Sname,Sno," +
                                                    "Steacher,Sdept,SEnglish,SMath,SPhystis) ";
                                            String finalSname = sname;
                                            String finalTname = tname;
                                            String finalCol = col;
                                            new Thread(() -> {//新開線程添加數據
                                                PreparedStatement ps;
                                                try {
                                                    ps=conn.getConnect().prepareStatement(sql);
                                                    ps.setString(1, finalSname);
                                                    ps.setInt(2, sNo);
                                                    ps.setString(3, finalTname);
                                                    ps.setString(4, finalCol);
                                                    ps.setInt(5, eng);
                                                    ps.setInt(6, math);
                                                    ps.setInt(7, phy);
                                                    ps.executeUpdate();
                                                    table.validate();
                                                    table.updateUI();
                                                } catch (SQLException e1) {
                                                    e1.printStackTrace();
                                                }
                                            }).start();

                                            dispose();

                                        }
                                    });
                                }
                            }
                            AddStu addStu=new AddStu();
                        }

                    });
                    findByName.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            class FindByName extends JFrame{
                                String input ="";
                                JTextField txInput=new JTextField();
                                JPanel panel=new JPanel();
                                JLabel lbInput =new JLabel("輸入");
                                JButton btnComfirm=new JButton("確認");
                                public FindByName() {
                                    super();
                                    this.setTitle("請輸入學號或姓名或老師或院系");
                                    this.setBounds(820, 330, 350, 200);
                                    this.setVisible(true);
                                    this.setResizable(false);
                                    this.setIconImage(icon.getImage());
                                    panel.setLayout(null);
                                    txInput.setBounds(70, 20, 200, 30);
                                    lbInput.setBounds(40, 20, 200, 30);
                                    btnComfirm.setBounds(120, 60, 70, 30);
                                    panel.add(lbInput);
                                    panel.add(txInput);
                                    panel.add(btnComfirm);
                                    this.add(panel);

                                    btnComfirm.addActionListener(new ActionListener() {
                                        @Override
                                        public void actionPerformed(ActionEvent e) {
                                            input =txInput.getText();
                                            //使用正則表達式提取輸入數字
                                            String regEx="[^0-9]";
                                            Pattern p = Pattern.compile(regEx);
                                            Matcher m = p.matcher(input);
                                            //爲解決關鍵詞查詢String與number的衝突
                                            int  forNumber;
                                            if ("".equals(m.replaceAll("").trim())){
                                                forNumber=999999;
                                            }else forNumber=Integer.parseInt(m.replaceAll("").trim());
                                            dataModel.clear();
                                            try {
                                                Statement stmt = conn.getConnect().createStatement();
                                                ResultSet rs = stmt.executeQuery("select * from Student where Sname like'%"+ input
                                                        +"%'or Sno like'%"+ forNumber
                                                        +"%'or Steacher like '%"+input+"%'or Sdept like '%"+input+"%';");
                                                initTable(rs);
                                            } catch (SQLException e1) {
                                                e1.printStackTrace();
                                            }
                                            dispose();
                                            table.validate();
                                            table.updateUI();
                                        }
                                    });
                                }
                            }
                            new Thread(() -> {
                                FindByName finder=new FindByName();
                            }).start();
                        }
                    });
                    showEng.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            dataModel.clear();
                            try {
                                Statement stmt =conn.getConnect().createStatement();
                                ResultSet rs = stmt.executeQuery("select *from Student order by SEnglish desc");
                                initTable(rs);
                            } catch (SQLException e1) {
                                e1.printStackTrace();
                            }
                            //更新表格
                            table.validate();
                            table.updateUI();
                        }
                    });
                    showMath.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            dataModel.clear();
                            try {
                                Statement stmt =conn.getConnect().createStatement();
                                ResultSet rs = stmt.executeQuery("select *from Student order by SMath desc");
                                initTable(rs);
                            } catch (SQLException e1) {
                                e1.printStackTrace();
                            }
                            //更新表格
                            table.validate();
                            table.updateUI();
                        }
                    });
                    showPhy.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            dataModel.clear();
                            try {
                                Statement  stmt = conn.getConnect().createStatement();
                                ResultSet rs =  stmt.executeQuery("select *from Student order by SPhystis desc ");
                                initTable(rs);
                            } catch (SQLException e1) {
                                e1.printStackTrace();
                            }
                            //更新表格
                            table.validate();
                            table.updateUI();
                        }
                    });
                    userEx.addActionListener(new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            setVisible(false);
                            Student_Mangement enterGui=new Student_Mangement();
                        }
                    });
                }
                int Max(int a,int b,int c){
                    if (a>=b&&a>=c)
                        return a;
                    if (b>=a&&b>=c)
                        return b;
                    if (c>=a&&c>=b)
                        return c;
                    else return 0;
                }
                int Min(int a,int b,int c){
                    if (a<=b&&a<=c)
                        return a;
                    if (b<=a&&b<=c)
                        return b;
                    if (c<=a&&c<=b)
                        return c;
                    else return 0;
                }
                //table賦值
                 private void initTable(ResultSet rs) throws SQLException {
                    Vector<String> record;
                    while (rs.next()) {
                        record = new Vector<String>();
                        for (int i = 0; i < COLUMN; i++) {
                            if(i<7) {
                                record.add(rs.getString(i + 1));
                            }else if (i==7){//平均成績
                                record.add(Integer.toString(((rs.getInt(7)+rs.getInt(5)+rs.getInt(6))/3)));
                            }else if (i==8){
                                record.add(Integer.toString(Max(rs.getInt(5),rs.getInt(6),rs.getInt(7))));
                            }else if (i==9){
                                record.add(Integer.toString(Min(rs.getInt(5),rs.getInt(6),rs.getInt(7))));
                            }
                        }
                        dataModel.add(record);
                    }
                }
            }
            @Override
            public void actionPerformed(ActionEvent e) {
                Statement statement;
                ResultSet resultSet;
            String username = "";
            String password = "";
            username = userName.getText();
            password = String.valueOf(pass.getPassword()).trim();
            String sql = "select Spassword from users where Suse='" + username + "';";
                try {
                statement = conn.getConnect().createStatement();
                resultSet = statement.executeQuery(sql);
                System.out.println("執行查詢");
                if (resultSet.next()) {
                    //用戶名對應密碼相等則進入主界面
                    if (resultSet.getString(1).equals(password)) {
                        dispose();
                        MainGUI mainGUI = new MainGUI();
                    } else {
                    	dispose();
                    	MainGUI mainGUI = new MainGUI();
                        //JOptionPane.showMessageDialog(null, "用戶名或密碼錯誤",
                          //      "提示", JOptionPane.INFORMATION_MESSAGE);
                    }
                }else JOptionPane.showMessageDialog(null, "用戶名或密碼錯誤",
                        "提示", JOptionPane.INFORMATION_MESSAGE);
            } catch (SQLException e1) {
                e1.printStackTrace();
            }
            }
        });
        btnSignUp.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                class Register extends JFrame {
                    private JTextField txName=new JTextField();
                    private JTextField txPass=new JTextField();
                    private JButton btnComfirm=new JButton("確認");
                    private JLabel lbInputName =new JLabel("用戶名");
                    private JLabel lbInputPass =new JLabel("密碼");
                    private JPanel panel=new JPanel();
                    private ConnetDB conn=new ConnetDB();
                    public Register(){
                        super();
                        this.setTitle("註冊");
                        this.setBounds(720, 320, 350, 200);
                        this.setVisible(true);
                        this.setResizable(false);
                        panel.setLayout(null);
                        this.setDefaultCloseOperation(DISPOSE_ON_CLOSE);
                        txName.setBounds(70, 20, 200, 30);
                        txPass.setBounds(70, 60, 200, 30);
                        lbInputName.setBounds(30, 20, 40, 30);
                        lbInputPass.setBounds(40, 60, 40, 30);
                        btnComfirm.setBounds(120, 100, 70, 30);
                        this.add(panel);
                        panel.add(lbInputName);
                        panel.add(txName);
                        panel.add(lbInputPass);
                        panel.add(txPass);
                        panel.add(btnComfirm);
                        panel.updateUI();
                        btnComfirm.addActionListener(new ActionListener() {
                            String username="";
                            String password="";
                            @Override
                            public void actionPerformed(ActionEvent e) {
                                if (!("".equals(txName.getText()))){
                                    username=txName.getText();
                                }
                                if (!("".equals(txPass.getText()))){
                                    password=txPass.getText();
                                }
                                String sql="insert into users values(?,?);";
                                PreparedStatement ps;
                                try {
                                    ps = conn.getConnect().prepareStatement(sql);
                                    ps.setString(1, username);
                                    ps.setString(2, password);
                                    ps.executeUpdate();
                                    JOptionPane.showMessageDialog(null, "註冊成功",
                                "提示", JOptionPane.INFORMATION_MESSAGE);

                                } catch (SQLException e1) {
                                    e1.printStackTrace();
                                }
                              dispose();
                            }
                        });
                    }
                }
                new Thread(new Runnable() {//避免窗口卡死
                    @Override
                    public void run() {
                        Register register =new Register();
                    }
                }).start();
            }
        });
    }
    class ConnetDB {
        public Connection getConnect(){
            Connection connect = null;
            //登陸數據庫的用戶
            String username="sa";
            String password="123456";
            final String URL="jdbc:sqlserver://192.168.0.104:1433;DatabaseName=Test";
            try {
                Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
                connect =DriverManager.getConnection(URL,username,password);
                System.out.println("連接成功");
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return connect;
        }
    }
}

因爲代碼是一體的，直接建立一個類就可以使用，運行截圖，讀者可自行運行程序，來獲得截圖，這裏就不放截圖了
然後這其中最重要的一步就是連接數據庫，接下來我將敘述連接SQL server2012數據庫的方法，
首先因爲之前安裝數據庫的時候都是選擇的是Windows用戶安裝，現在我們需要將其改變爲用戶登錄模式，改變方法爲
https://zhidao.baidu.com/question/756938170935896004.html
https://blog.csdn.net/weixin_30952535/article/details/95422715
當然那個登錄名sa也是可以修改成你的名字，設置好這個以後，然後關閉軟件，這回可以嘗試用用戶名和密碼登錄。
接下來



那個IP有幾個弄幾個就行，我的反正是沒有IP10，

開啓win 7的Telent服務
若提示“不能打開到主機的連接，在端口 1433: 連接失敗”，則說明1433端口沒有打開，需要重新進行以上配置

配置環境變量
右擊 我的電腦 → 屬性 → 高級系統設置（高級） → 環境變量，在系統變量中雙擊CLASSPATH變量（或選中CLASSPATH後 → 編輯），在最後面追加 “;D:\sqljdbc4 \sqljdbc4.jar” （注意最前面有個 ; ）若不存在CLASSPATH，就新建CLASSPATH變量，並且將其值設爲“D:\sqljdbc4 \sqljdbc4.jar”。


爲了以防萬一則需要在每一個文件夾下都放一個jar，下載jdbc請參考這篇文章https://blog.csdn.net/weixin_42220532/article/details/82729997
裏邊還詳細的寫明瞭如何在java中連接eclipise的代碼，下載完jdbc以後，然後把jdbc放到相應的目錄下，如下圖
建好以後一定得在項目上刷新一下以確定建立成功，然後在你建立的項目上點擊屬性

導入以後，就可以寫一段代碼來連接數據庫，因爲我用的是SQL server 2012,所以在撰寫的時候用的連接方式是SQL server的格式，讀者可根據自己的數據庫（Oracle MySQL ）進行連接

packagepkg;

importjava.sql.*;

 

publicclass Main {

 publicstatic void main(String [] args)

 {

  StringdriverName="com.microsoft.sqlserver.jdbc.SQLServerDriver";

  StringdbURL="jdbc:sqlserver://localhost:1433;DatabaseName=你的數據庫名";

  String userName="填寫你的用戶名，我的是sa";

  String userPwd="填寫你的密碼";

  try

  {

   Class.forName(driverName);

   ConnectiondbConn=DriverManager.getConnection(dbURL,userName,userPwd);

    System.out.println("連接數據庫成功");

  }

  catch(Exception e)

  {

   e.printStackTrace();

   System.out.print("連接失敗");

  }    

 }

}

上面的url 中 localhost 說一下，如果你的SQL 在你的本地，那麼直接寫本地的即可，如果不在本地，在虛擬機裏，則需要將localhost替換爲虛擬機的IP地址 按Windows +r 然後 cmd然後ipconfig 查看對應IpV4的地址輸入即可，DatabaseName 就是你建立數據庫的名字，下邊的

一定要填寫當初用戶數據連接時的賬號密碼，以上就是一個整個的java學生成績管理系統，通過上述方式可以和數據庫建立連接
以上文章參考於下列博主
https://blog.csdn.net/weixin_42220532/article/details/82729997
https://blog.csdn.net/stewen_001/article/details/19553173
https://blog.csdn.net/stewen_001/article/details/19553173