5.4 员工管理系统之CRUD、错误页面以及注销功能

一.员工信息列表展示

1.步骤：

• 提取公共页面

• 编写控制器

• 列表循环展示

2.提取公共页面

（1）在template文件夹下建立common文件夹添加文件commons.html，将公共部分抽取出来

• 使用 th:fragment="topbar" ， th:fragment="sidebar" 将代码块生成片段

• 其中 <a th:class="${active == 'main.html' ? 'nav-link active' : 'nav-link'}" th:href="@{/main.html}"> 和

   <a th:class="${active == 'list.html' ? 'nav-link active' : 'nav-link'}" th:href="@{/emps}"> 目的是从其他页面调用公共页面的片段可以传递参数，此处参数是为了高亮显示，如果用户点击首页则首页列表项显示高亮，如果用户点击员工管理页则其显示为高亮

<!--顶部导航栏-->
<nav class="navbar navbar-dark sticky-top bg-dark flex-md-nowrap p-0" th:fragment="topbar">
    <a class="navbar-brand col-sm-3 col-md-2 mr-0" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#" th:text="${session.loginUser}"></a>
    <input class="form-control form-control-dark w-100" type="text" placeholder="Search" aria-label="Search">
    <ul class="navbar-nav px-3">
        <li class="nav-item text-nowrap">
            <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">注销</a>
        </li>
    </ul>
</nav>

<!--侧边栏-->
<nav class="col-md-2 d-none d-md-block bg-light sidebar" th:fragment="sidebar">
    <div class="sidebar-sticky">
        <ul class="nav flex-column">
            <li class="nav-item">

                <a th:class="${active == 'main.html' ? 'nav-link active' : 'nav-link'}" th:href="@{/main.html}">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-home">
                        <path d="M3 9l9-7 9 7v11a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2z"></path>
                        <polyline points="9 22 9 12 15 12 15 22"></polyline>
                    </svg>
                    首页 <span class="sr-only">(current)</span>
                </a>

            </li>
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-file">
                        <path d="M13 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V9z"></path>
                        <polyline points="13 2 13 9 20 9"></polyline>
                    </svg>
                    Orders
                </a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-shopping-cart">
                        <circle cx="9" cy="21" r="1"></circle>
                        <circle cx="20" cy="21" r="1"></circle>
                        <path d="M1 1h4l2.68 13.39a2 2 0 0 0 2 1.61h9.72a2 2 0 0 0 2-1.61L23 6H6"></path>
                    </svg>
                    Products
                </a>
            </li>
            <li class="nav-item">
                <a th:class="${active == 'list.html' ? 'nav-link active' : 'nav-link'}" th:href="@{/emps}">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-users">
                        <path d="M17 21v-2a4 4 0 0 0-4-4H5a4 4 0 0 0-4 4v2"></path>
                        <circle cx="9" cy="7" r="4"></circle>
                        <path d="M23 21v-2a4 4 0 0 0-3-3.87"></path>
                        <path d="M16 3.13a4 4 0 0 1 0 7.75"></path>
                    </svg>
                    员工管理
                </a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-bar-chart-2">
                        <line x1="18" y1="20" x2="18" y2="10"></line>
                        <line x1="12" y1="20" x2="12" y2="4"></line>
                        <line x1="6" y1="20" x2="6" y2="14"></line>
                    </svg>
                    Reports
                </a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-layers">
                        <polygon points="12 2 2 7 12 12 22 7 12 2"></polygon>
                        <polyline points="2 17 12 22 22 17"></polyline>
                        <polyline points="2 12 12 17 22 12"></polyline>
                    </svg>
                    Integrations
                </a>
            </li>
        </ul>

        <h6 class="sidebar-heading d-flex justify-content-between align-items-center px-3 mt-4 mb-1 text-muted">
            <span>Saved reports</span>
            <a class="d-flex align-items-center text-muted" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-plus-circle"><circle cx="12" cy="12" r="10"></circle><line x1="12" y1="8" x2="12" y2="16"></line><line x1="8" y1="12" x2="16" y2="12"></line></svg>
            </a>
        </h6>
        <ul class="nav flex-column mb-2">
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-file-text">
                        <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"></path>
                        <polyline points="14 2 14 8 20 8"></polyline>
                        <line x1="16" y1="13" x2="8" y2="13"></line>
                        <line x1="16" y1="17" x2="8" y2="17"></line>
                        <polyline points="10 9 9 9 8 9"></polyline>
                    </svg>
                    Current month
                </a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-file-text">
                        <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"></path>
                        <polyline points="14 2 14 8 20 8"></polyline>
                        <line x1="16" y1="13" x2="8" y2="13"></line>
                        <line x1="16" y1="17" x2="8" y2="17"></line>
                        <polyline points="10 9 9 9 8 9"></polyline>
                    </svg>
                    Last quarter
                </a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-file-text">
                        <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"></path>
                        <polyline points="14 2 14 8 20 8"></polyline>
                        <line x1="16" y1="13" x2="8" y2="13"></line>
                        <line x1="16" y1="17" x2="8" y2="17"></line>
                        <polyline points="10 9 9 9 8 9"></polyline>
                    </svg>
                    Social engagement
                </a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="http://getbootstrap.com/docs/4.0/examples/dashboard/#">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-file-text">
                        <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"></path>
                        <polyline points="14 2 14 8 20 8"></polyline>
                        <line x1="16" y1="13" x2="8" y2="13"></line>
                        <line x1="16" y1="17" x2="8" y2="17"></line>
                        <polyline points="10 9 9 9 8 9"></polyline>
                    </svg>
                    Year-end sale
                </a>
            </li>
        </ul>
    </div>
</nav>

（2）在dashboard.html和list.html中使用片段：th:replace="~{xxx}"

• 向公共部分传递参数：使用小括号包含，中间使用键值对赋值 (active='main.html') ，此处active目的是被点到的列表项显示高亮

<!--顶部导航栏-->
<div th:replace="~{common/commons::topbar}"></div>

<!--侧边栏-->
<div th:replace="~{common/commons::sidebar(active='main.html')}"></div>

3.编写控制器

添加EmployeeController.java

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import ustc.wzh.dao.EmployeeDao;
import ustc.wzh.pojo.Employee;

import java.util.Collection;

@Controller
public class EmployeeController {

    @Autowired
    EmployeeDao employeeDao;

    //查询所有员工，返回列表页面
    @GetMapping("/emps")
    public String list(Model model){
        Collection<Employee> employees = employeeDao.getAll();
        //将结果放在请求中
        model.addAttribute("emps",employees);
        return "emp/list";
    }

}

4.列表循环展示

• Thymeleaf的循环： th:each="emp:${emps}" ，emps为后台传递来的数据，emp为循环变量

• Thymeleaf自带的日期处理工具： th:text="${#dates.format(emp.birth,'yyyy-MM-dd HH:mm')}" 

<div class="table-responsive">
    <table class="table table-striped table-sm">
        <thead>
            <tr>
                <th>id</th>
                <th>lastName</th>
                <th>email</th>
                <th>gender</th>
                <th>department</th>
                <th>birth</th>
            </tr>
        </thead>
        <tbody>
            <tr th:each="emp:${emps}">
                <td th:text="${emp.id}"></td>
                <td>[[${emp.lastName}]]</td>
                <td th:text="${emp.email}"></td>
                <td th:text="${emp.gender==0?'女':'男'}"></td>
                <td th:text="${emp.department.departmentName}"></td>
                <!--<td th:text="${emp.birth}"></td>-->
                <!--使用时间格式化工具-->
                <td th:text="${#dates.format(emp.birth,'yyyy-MM-dd HH:mm')}"></td>

                <!--操作-->
                <td>
                    <button class="btn btn-sm btn-primary">编辑</button>
                    <button class="btn btn-sm btn-danger">删除</button>
                </td>
            </tr>
        </tbody>
    </table>
</div>

二.添加员工信息

1.步骤：

• 添加按钮用于跳转到添加员工信息页面

• 编写员工信息添加页面

• 添加控制器方法

• 配置文件中修改日期格式

2.添加按钮用于跳转到添加员工信息页面

•  th:href="@{/emp}" 默认为get请求跳转到 @GetMapping("/emp") 方法中

<!--添加员工按钮-->
<h2> <a class="btn btn-sm btn-success"th:href="@{/emp}">添加员工</a></h2>

3.编写员工信息添加页面

•  th:action="@{/emp}" method="post" 使用post方法跳转到 @PostMapping("/emp") 方法中

• 需要提交的信息需要name属性

• 部门显示内容使用部门名称，value为部门id，还要thymeleaf的循环表达式：
   th:each="dept:${departments}" th:text="${dept.departmentName}" th:value="${dept.id}" 

• 部门提交时使用部门id： name="department.id" 

<h2>添加员工</h2>
<form th:action="@{/emp}" method="post">
    <div class="form-group">
        <label>LastName</label>
        <input type="text" name="lastName" class="form-control" placeholder="kuangshen">
    </div>
    <div class="form-group">
        <label>Email</label>
        <input type="email" name="email" class="form-control" placeholder="24736743@qq.com">
    </div>
    <div class="form-group">
        <label>Gender</label><br/>
        <div class="form-check form-check-inline">
            <input class="form-check-input" type="radio" name="gender"  value="1">
            <label class="form-check-label">男</label>
        </div>
        <div class="form-check form-check-inline">
            <input class="form-check-input" type="radio" name="gender"  value="0">
            <label class="form-check-label">女</label>
        </div>
    </div>
    <div class="form-group">
        <label>department</label>
        <!--提交的是部门的ID-->
        <select class="form-control" name="department.id">
            <option th:each="dept:${departments}" th:text="${dept.departmentName}" th:value="${dept.id}"></option>
        </select>
    </div>
    <div class="form-group">
        <label>Birth</label>
        <input type="text" name="birth" class="form-control" placeholder="kuangstudy">
    </div>
    <button type="submit" class="btn btn-primary">添加</button>
</form>

4.添加控制器方法

• 使用RestFul风格提交方式 @PostMapping("/emp") ， @GetMapping("/emp") 

@Autowired
DepartmentDao departmentDao;

//跳转到员工添加页面
@GetMapping("/emp")
public String toAddPage(Model model){
    //查出所有的部门，提供选择
    Collection<Department> departments = departmentDao.getDepartments();
    model.addAttribute("departments",departments);
    return "emp/add";
}

//员工添加功能
//接收前端传递的参数，自动封装成为对象[要求前端传递的参数名，和属性名一致]
@PostMapping("/emp")
public String addEmp(Employee employee){
    System.out.println(employee);
    employeeDao.save(employee); //保存员工信息
    //回到员工列表页面，可以使用redirect或者forward
    return "redirect:/emps";
}

5.配置文件中修改日期格式

• 一旦修改就不能使用原来的yyyy/MM/dd的方式提交

# 设置日期格式
spring.mvc.date-format=yyyy-MM-dd

三.员工信息修改

1.步骤：

• 修改编辑按钮

• 添加修改页面

• 添加控制器方法

• 修改日期格式

2.修改编辑按钮

• 跳转路径 th:href="@{/emp/}+${emp.id}" ，Restful风格的参数传递

<a class="btn btn-sm btn-primary" th:href="@{/emp/}+${emp.id}">编辑</a>

• 官网文档推荐 th:href="@{/emp/{id}(id=${emp.id})}" 

<a class="btn btn-sm btn-primary" th:href="@{/emp/{id}(id=${emp.id})}">编辑</a>

3.添加修改页面

•  th:action="@{/updateEmp}" method="post" ，跳转路径和post提交方式

•  type="hidden" th:value="${emp.id}" ，隐藏值传回id值

•  th:value="${emp.getLastName()}" ，input标签填充值

•  th:checked="${emp.gender==1}" ，判断选择哪一个单选框

•  th:selected="${dept.getId() == emp.getDepartment().getId()}" ，获得下拉列表中的值

•  th:value="${#dates.format(emp.birth,'yyyy-MM-dd HH:mm:ss')}" ，设置日期值

<main role="main" class="col-md-9 ml-sm-auto col-lg-10 pt-3 px-4">
    <h2>修改员工信息</h2>
    <form th:action="@{/updateEmp}" method="post">
        <input name="id" type="hidden" class="form-control" th:value="${emp.id}">
        <div class="form-group">
            <label>LastName</label>
            <input th:value="${emp.getLastName()}" type="text" name="lastName" class="form-control" placeholder="kuangshen">
        </div>
        <div class="form-group">
            <label>Email</label>
            <input th:value="${emp.getEmail()}" type="email" name="email" class="form-control" placeholder="24736743@qq.com">
        </div>
        <div class="form-group">
            <label>Gender</label><br/>
            <div class="form-check form-check-inline">
                <input  th:checked="${emp.gender==1}"  class="form-check-input" type="radio" name="gender" value="1">
                <label class="form-check-label">男</label>
            </div>
            <div class="form-check form-check-inline">
                <input th:checked="${emp.gender==0}" class="form-check-input" type="radio" name="gender"  value="0">
                <label class="form-check-label">女</label>
            </div>
        </div>
        <div class="form-group">
            <label>department</label>
            <!--提交的是部门的ID-->
            <select class="form-control" name="department.id">
                <option th:selected="${dept.getId() == emp.getDepartment().getId()}" th:each="dept:${departments}" th:text="${dept.departmentName}" th:value="${dept.id}"></option>
            </select>
        </div>
        <div class="form-group">
            <label>Birth</label>
            <input type="text" name="birth" class="form-control" th:value="${#dates.format(emp.birth,'yyyy-MM-dd HH:mm:ss')}" placeholder="kuangstudy">
        </div>
        <button type="submit" class="btn btn-primary">修改</button>
    </form>
</main>

4.添加控制器方法

//跳转到员工修改页面
@GetMapping("/emp/{id}")
public String toUpdateEmp(@PathVariable("id") Integer id, Model model){
    //根据id查出来员工
    Employee employee = employeeDao.get(id);
    //将员工信息返回页面
    model.addAttribute("emp",employee);
    //查出所有的部门，提供修改选择
    Collection<Department> departments = departmentDao.getDepartments();
    model.addAttribute("departments",departments);

    return "emp/update";
}

// 修改员工信息
@PostMapping("/updateEmp")
public String updateEmp(Employee employee){
    employeeDao.save(employee);
    //回到员工列表页面
    return "redirect:/emps";
}

5.修改日期格式

# 设置日期格式
spring.mvc.date-format=yyyy-MM-dd HH:mm:ss

四.员工信息删除

1.步骤：

• 添加删除按钮

• 添加控制器方法

2.添加删除按钮

<a class="btn btn-sm btn-danger" th:href="@{/delEmp/{id}(id=${emp.id})}">删除</a>

3.添加控制器方法

@GetMapping("/delEmp/{id}")
public String delEmp(@PathVariable("id") Integer id){
    employeeDao.delete(id);
    return "redirect:/emps";
}

五.错误页面

1.在template目录下添加error文件夹

• 添加404.html等错误页面即可，springboot会自动定位

六.注销功能

1.步骤：

• 编写注销按钮

• 控制器添加方法

2.编写注销按钮

<a class="nav-link" th:href="@{/user/loginOut}">注销</a>

3.控制器添加方法

• 在LoginController中添加方法

@GetMapping("/user/loginOut")
public String loginOut(HttpSession session){
    session.invalidate();
    return "redirect:/index.html";
}