数据库增删改查

程序员文章站 2022-06-23 11:44:13

编写一个学生注册的页面

<head>
    <title>注册页面</title>
    <link rel="stylesheet" href="css/bootstrap.css">

    <script src="js/jquery.min.js"></script>
    <script src="js/bootstrap.js"></script>
    <script src="js/bootstrap.bundle.js"></script>
    <style>
        .container{
            width: 20%;
            height: 20%;
            margin-top: 10%;
        }
    </style>
</head>
<body>
<div class="container">
    <div class="row clearfix">
        <div class="col-md-12 column">
<form action="register.jsp" method="post">
    用户名:<input type="text" name="username" class="form-control"><br>
    密码：<input type="text" name="password" class="form-control"><br>
    性别：<input type="text" name="gender" class="form-control"><br>
    年龄：<input type="text" name="age" class="form-control"><br>
    <button type="submit">注册</button>
</form>
        </div>
    </div>
</div>
</body>

数据库增删改查

注册成功提示页面

<jsp:useBean id="user" class="com.media.bean.userbean"></jsp:useBean>
<jsp:setProperty name="user" property="*"></jsp:setProperty>

<%
    Class.forName("com.mysql.jdbc.Driver");
    String url = "jdbc:mysql://localhost:3306/book";
    Connection connection = DriverManager.getConnection(url,"root","root");
    Statement stmt = connection.createStatement();
    String sql = "inser into user(username,password,gender,age) valuse("+user.getUsername()+","+user.getPassword()+",1,20)";
    int count = stmt.executeUpdate(sql);
    if(count >0){
        out.print("注册成功");
    }else{
        out.print("注册失败");
    }
%>

编写一个登录页面，建立一个登陆的表单

<html>
<head>
    <title>登录页面</title>
    <%--引入css文件和js文件--%>
    <link rel="stylesheet" href="css/bootstrap.css">

    <script src="js/jquery.min.js"></script>
    <script src="js/bootstrap.js"></script>
    <script src="js/bootstrap.bundle.js"></script>

    <style>
        .container{
            width: 20%;
            height: 20%;
            margin-top: 10%;
        }
    </style>
</head>
<body>
<div class="container">
    <div class="row clearfix">
        <div class="col-md-12 column">
            <form role="form" method="post" action="index.jsp">
                <h3 style="text-align: center"登录></h3>
                <div class="form-group">
                    <label for="exampleInputEmail1">用户名：</label><input name="username" class="form-control" id="exampleInputEmail1" type="text" />
                </div>
                <div class="form-group">
                    <label for="exampleInputPassword1">密码：</label><input name="password" class="form-control" id="exampleInputPassword1" type="password" />
                </div>
                <button class="btn btn-default" type="submit">提交</button>
            </form>
        </div>
    </div>
</div>
</body>
</html>

数据库增删改查

连接book数据库

//加载驱动
Class.forName("com.mysql.jdbc.Driver");

//建立数据库连接
String url = "jdbc:mysql://localhost:3306/book";//数据库连接地址
Connection connection = DriverManager.getConnection(url, "root", "root");
String sql = "select * from user where username = ? and password = ?";
//使用PreparedStatement对象执行sql语句
PreparedStatement ps = connection.prepareStatement(sql);

删除数据库操作代码如下：

//stmt.executeUpdate()执行删改的驱动
String sql = "delete from user where id=?";
PreparedStatement ps = connection.prepareStatement(sql);

int id = Integer.parseInt(request.getParameter("id"));

ps.setInt(1,id);

int count = ps.executeUpdate();

if (count > 0){
    out.print("删除成功");
}else{
    out.print("删除失败");
}

编辑数据库操作页面的代码：

String sql = "select * from user where id=?";
PreparedStatement ps = connection.prepareStatement(sql);

ps.setInt(1,id);

ResultSet rs = ps.executeQuery();

while (rs.next()){
    out.print("<input type='hidden' name='id' value="+rs.getString("id")+">");
    out.print("用户名:<input type='text' class='form-control' name='username' value="+rs.getString("username")+"><br>");
    out.print("密码:<input type='text' class='form-control' name='password' value="+rs.getString("password")+"><br>");
    out.print("性别:<input type='text' class='form-control' name='gender' value="+rs.getString("gender")+"><br>");
    out.print("年龄:<input type='text' class='form-control' name='age' value="+rs.getString("age")+"><br>");
}
 <button type="submit" style="width: 100%" class="btn btn-info">提交</button>
            </form>
        </div>
    </div>
</div>

数据库增删改查

编辑成功提示页面

//stmt.executeUpdate()执行修改的驱动
String sql = "update user set username = ?, password = ?,gender = ?,age = ? where id = ?";
PreparedStatement ps = connection.prepareStatement(sql);

ps.setString(1,user.getUsername());
ps.setString(2,user.getUsername());
ps.setInt(3,user.getGender());
ps.setInt(4,user.getAge());
ps.setInt(5,user.getId());

int count = ps.executeUpdate();

if (count >0){
    out.print("修改成功");
}else{
    out.print("修改失败");
}

写一个添加用户的表单：

 <div class="modal fade" id="modal-container-addUser" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
                <div class="modal-dialog">
                    <div class="modal-content">
                        <div class="modal-header">
                            <h4 class="modal-title" id="myModalLabel">添加用户</h4>
                            <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
                        </div>
                        <form role="form" method="post" action="add.jsp">
                            <div class="modal-body">
                                <div class="form-group">
                                    <label>用户名:</label><input type="text" name="username" class="form-control" />
                                </div>
                                <div class="form-group">
                                    <label>密码:</label><input type="password" name="password" class="form-control" />
                                </div>
                                <div class="form-group">
                                    <label>性别:</label><input type="text" name="gender" class="form-control" />
                                </div>
                                <div class="form-group">
                                    <label>年龄:</label><input type="text" name="age" class="form-control" />
                                </div>
                            </div>
                            <div class="modal-footer">
                                <button type="button" class="btn btn-default" data-dismiss="modal">关闭</button>
                                <button type="submit" class="btn btn-primary">添加</button>
                            </div>
                        </form>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>

数据库增删改查
添加成功提示页面的代码：

  String sql = "insert into user (username,password,gender,age) values (?,?,?,?)";
    PreparedStatement ps = connection.prepareStatement(sql);

    ps.setString(1,user.getUsername());
    ps.setString(2,user.getUsername());
    ps.setInt(3,user.getGender());
    ps.setInt(4,user.getAge());

    int count = ps.executeUpdate();

    if (count >0){
        out.print("添加成功");
    }else{
        out.print("添加失败");
    }
    response.setHeader("refresh","3;url=home.jsp");

本文地址：https://blog.csdn.net/xiao_feiy/article/details/109238426

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