2023.10.9课堂测试-526互联

javaweb代码连接数据库

使用的是jsp类型的的文件，jsp类型的文件可以包含javaweb页面和Java类型的代码

首先将MySQL的connector导入到项目的库中

在模块栏中点击依赖再点击左上角的+号

点击第一个后找到自己刚刚创建的lib文件夹

点击确定后点击应用再点击确定

然后再在第一个jsp文件中完成页面的输入框等

再在第二个jsp文件中完成读取数据和存入数据库

<%@ page contentType="text/html; charset=UTF-8" language="java" pageEncoding="UTF-8" %>

<?php include('connect.php'); ?>
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>测试登录页面</title>
    <style>
        body{
            width: 100%;
            background-repeat:no-repeat;
            background-size:100% ;
        }
        .login{
            float:right;
            margin-right:20vh;
            margin-top:15vh;
            opacity:0.7;
            height: 35vh;
            width:50vh;
            background:#CCFF80;
            border-radius: 20px;
        }
        .title{
            font-size:30px;
            text-align:center;
        }
        .biao{
            margin-top:20px;
            font-size:20px;
            text-align:center;
        }
    </style>
</head>
<body>
<div>
    <div class='login'>
        <div class='title'>欢迎登录</div>
        <div class='biao'>
            <form action="putin.jsp" method='post'>
                课程名称：<input type="text" name='course_name'><br><br>
                任课教师：<input type="text" name='instructor'><br><br>
                上课地点：<label>
                <select name="classroom">
                <option value="一教">一教</option>
                <option value="二教">二教</option>
                <option value="三教">三教</option>
                <option value="基教">基教</option>
            </select>
            </label><br><br>
                <input type="submit" value='添加' style='width:240px;height:30px;margin-top:25px;background:#B7FF4A'>
            </form>
        </div>
    </div>
</div>
</body>
</html>

<%@ page import="java.sql.*" %>
<%@ page contentType="text/html; charset=UTF-8" language="java" pageEncoding="UTF-8" %>
<%
  request.setCharacterEncoding("UTF-8");
  String  hey = "请重新录入";
  String classname = request.getParameter("course_name");
  String teacher = request.getParameter("instructor");
  String place = request.getParameter("classroom");
  System.out.println(place);
  try {
    Class.forName("com.mysql.cj.jdbc.Driver");
    String url = "jdbc:mysql://localhost:3306/data?useSSL=false&characterEncoding=UTF8";
    String name = "root";
    String password = "123456";
    Connection conn = DriverManager.getConnection(url, name, password);
    Statement st;
    String sqlsearch = "select count(*) from class where classname= '" + classname + "'";
    PreparedStatement ps = conn.prepareStatement(sqlsearch);
    st = conn.createStatement();
    ResultSet re = st.executeQuery(sqlsearch);
    re.next();
    int count = re.getInt(1);

    hey = "保存成功";
    String sql = "insert into class(classname,teacher,place) values(?,?,?)";//数据库操作语句（插入）
    PreparedStatement pst = conn.prepareStatement(sql);//用来执行SQL语句查询，对sql语句进行预编译处理
    pst.setString(1, classname);
    pst.setString(2, teacher);
    pst.setString(3, place);
    pst.executeUpdate();//解释在下
    System.out.print("数据库连接成功");
    conn.close();
    request.setAttribute("hey", hey);
  } catch (Exception e) {
    System.out.println("数据库连接失败");
    System.out.println("错误信息：" + e);
  }
%>
<html>
<body style="background: blanchedalmond">
<div style="text-align: center" class="container text-center">
  <h2 class="form-signin-heading" style="color: brown">
    <font size=10>
      <strong>
        ${hey}
      </strong>
    </font>
  </h2>
  <form action="index.jsp">
    <input type="submit" value="返回" style="color: darkblue;font-size:35px;background:khaki;border-radius: 15px" >
  </form>
</div>
</body>
</html>