From 97e1d197dd9b694b1c9d1439707d78c639136362 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=B1=BD=E5=A2=83?= <1537282342@qq.com>
Date: Sun, 28 May 2023 22:56:54 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BD=9C=E4=B8=9A?=
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---
 ...7\346\234\254\346\226\207\346\241\243.txt" | 252 ++++++++++++++++++
 1 file changed, 252 insertions(+)
 create mode 100644 "28 \351\273\204\346\242\223\345\242\203/29239528/\346\226\260\345\273\272\346\226\207\346\234\254\346\226\207\346\241\243.txt"

diff --git "a/28 \351\273\204\346\242\223\345\242\203/29239528/\346\226\260\345\273\272\346\226\207\346\234\254\346\226\207\346\241\243.txt" "b/28 \351\273\204\346\242\223\345\242\203/29239528/\346\226\260\345\273\272\346\226\207\346\234\254\346\226\207\346\241\243.txt"
new file mode 100644
index 0000000..21243fa
--- /dev/null
+++ "b/28 \351\273\204\346\242\223\345\242\203/29239528/\346\226\260\345\273\272\346\226\207\346\234\254\346\226\207\346\241\243.txt"	
@@ -0,0 +1,252 @@
+package sql;
+
+import jakarta.servlet.*;
+import jakarta.servlet.http.*;
+import jakarta.servlet.annotation.*;
+import tools.Jdbc;
+
+import java.io.IOException;
+
+@WebServlet(name = "Delete", value = "/Delete")
+public class Delete extends HttpServlet {
+    @Override
+    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        request.setCharacterEncoding("utf-8");
+        response.setContentType("text/html;charset=utf-8");
+        String id = request.getParameter("id");
+        System.out.println(id);
+        int i = Jdbc.update("delete from student where id=?", id);
+        if (i>0){
+            response.getWriter().write("<script>alert('删除成功');location.href='/index.jsp'</script>");
+        }else {
+            response.getWriter().write("<script>alert('删除失败');location.href='/index.jsp'</script>");
+        }
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+
+    }
+}
+
+package sql;
+
+public class Student {
+    private String id;
+    private String name;
+
+    public Student() {
+    }
+
+    public Student(String id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}
+
+package sql;
+
+import jakarta.servlet.*;
+import jakarta.servlet.http.*;
+import jakarta.servlet.annotation.*;
+import tools.Jdbc;
+
+import java.io.IOException;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+@WebServlet(name = "Update", value = "/Update")
+public class Update extends HttpServlet {
+    @Override
+    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        request.setCharacterEncoding("utf-8");
+        response.setContentType("text/html;charset=utf-8");
+        String id = request.getParameter("id");
+        try {
+            ResultSet re = Jdbc.select("select * from student where id=?", id);
+            re.next();
+            Student s = new Student(re.getString(1), re.getString(2));
+            request.setAttribute("student",s);
+            request.getRequestDispatcher("/update.jsp").forward(request,response);
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+
+    }
+}
+
+package sql;
+
+import jakarta.servlet.*;
+import jakarta.servlet.http.*;
+import jakarta.servlet.annotation.*;
+import tools.Jdbc;
+
+import java.io.IOException;
+
+@WebServlet(name = "Update2", value = "/Update2")
+public class Update2 extends HttpServlet {
+    @Override
+    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        doPost(request, response);
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        request.setCharacterEncoding("utf-8");
+        response.setContentType("text/html;charset=utf-8");
+        String id = request.getParameter("id");
+        String name = request.getParameter("name");
+        int i = Jdbc.update("update student set name=? where id=?", name, id);
+        if (i > 0) {
+            response.getWriter().write("<script>alert('修改成功');location.href='/index.jsp'</script>");
+        } else {
+            response.getWriter().write("<script>alert('修改失败');location.href='/index.jsp'</script>");
+        }
+    }
+}
+
+package tools;
+
+import java.sql.*;
+
+public class Jdbc {
+    static {
+        try {
+            Class.forName("com.mysql.jdbc.Driver");
+        } catch (ClassNotFoundException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    //创建连接
+    private static Connection conn() {
+        String url = "jdbc:mysql://localhost:3306/text?useSSL=false&useUnicode=true&characterEncoding=utf8";
+        Connection conn = null;
+        try {
+            conn = DriverManager.getConnection(url, "root", "sxxddytdn");
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+        return conn;
+    }
+
+    //查询
+    public static ResultSet select(String sql, String... arr) {
+        ResultSet re = null;
+        try {
+            PreparedStatement pst = conn().prepareStatement(sql);
+            for (int i = 0; i < arr.length; i++) {
+                pst.setString((i + 1), arr[i]);
+            }
+            re = pst.executeQuery();
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+        return re;
+    }
+
+    //增删改
+    public static int update(String sql, String... arr) {
+        try {
+            PreparedStatement pst = conn().prepareStatement(sql);
+            for (int i = 0; i < arr.length; i++) {
+                pst.setString((i + 1), arr[i]);
+            }
+            int i = pst.executeUpdate();
+            return i;
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+    }
+}
+```
+
+```jsp
+<%@ page import="java.sql.ResultSet" %>
+<%@ page import="tools.Jdbc" %><%--
+  Created by IntelliJ IDEA.
+  User: NO.1
+  Date: 2023/5/19
+  Time: 17:03
+  To change this template use File | Settings | File Templates.
+--%>
+<%@ page contentType="text/html;charset=UTF-8" language="java" %>
+<html>
+<head>
+    <title>学生列表</title>
+</head>
+<style>
+    * {
+        text-align: center;
+    }
+</style>
+<body>
+<table border="1" width="500">
+    <tr>
+        <th>编号</th>
+        <th>姓名</th>
+        <th>操作</th>
+    </tr>
+
+    <%
+        ResultSet re = Jdbc.select("select * from student");
+        while (re.next()) {
+            String id = re.getString(1);
+            String name = re.getString(2);
+    %>
+    <tr>
+        <td><%=id%></td>
+        <td><%=name%></td>
+        <td><a href="/Update?id=<%=id%>">修改</a>&nbsp;<a href="/Delete?id=<%=id%>">删除</a></td>
+    </tr>
+    <%
+        }
+    %>
+</table>
+</body>
+</html>
+
+<%@ page import="sql.Student" %><%--
+  Created by IntelliJ IDEA.
+  User: NO.1
+  Date: 2023/5/28
+  Time: 20:29
+  To change this template use File | Settings | File Templates.
+--%>
+<%@ page contentType="text/html;charset=UTF-8" language="java" %>
+<html>
+<head>
+    <title>修改</title>
+</head>
+<body>
+<%
+    Student s = (Student) request.getAttribute("student");
+%>
+<form action="/Update2" method="post">
+    <input type="hidden" name="id" value="<%=s.getId()%>"><br>
+    姓名： <input type="text" name="name" value="<%=s.getName()%>"><br>
+    <input type="submit" value="修改">
+</form>
+</body>
+</html>
\ No newline at end of file
-- 
Gitee