【学员管理系统】0x03 老师信息管理功能

【学员管理系统】0x03 老师信息管理功能

老师信息管理相比于学生信息管理又多了一点，因为我们的数据结构中老师表和班级表是通过teacher2class表进行多对多关联的。

写在前面

项目详细需求参见：Django项目之【学员管理系统】

展示老师信息

后端部分

注意连表查询操作

def teacher_list(request):
    # 连接数据库
    conn = pymysql.connect(host="127.0.0.1", port=3306, user="root", passwd="root1234", db="mysite", charset="utf8")
    cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
    sql = "select teacher.id, teacher.name, class.name as cname from teacher LEFT JOIN teacher2class on teacher.id = teacher2class.teacher_id LEFT JOIN class ON teacher2class.class_id = class.id;"
    cursor.execute(sql)
    teacher_list_o = cursor.fetchall()
    # 将查询到的数据类型转换一下
    teacher_list = magic(teacher_list_o)
    return render(request, "teacher_list.html", {"teacher_list": teacher_list})

前端部分

将老师关联的班级信息也展示出来。

<table class="table table-bordered table-striped">
  <thead>
  <tr>
    <th>#</th>
    <th>老师</th>
    <th>班级</th>
    <th>操作</th>
  </tr>
  </thead>
  <tbody>
  {% for teacher in teacher_list %}
  <tr>
    <th scope="row">{{ teacher.id }}</th>
    <td>{{ teacher.name }}</td>
    <td>
      {% for class in teacher.class_list %}
      <span>{{ class }}</span>|
      {% endfor %}
    </td>
    <td class="text-center">
      <a type="button" class="btn btn-sm btn-success m-edit" aria-label="Left Align">
        <span class="glyphicon glyphicon-pencil" aria-hidden="true"></span>编辑
      </a>
      |
      <a href="/edit_teacher/?teacher_id={{ teacher.id }}/" type="button" class="btn btn-sm btn-success" aria-label="Left Align">
        <span class="glyphicon glyphicon-pencil" aria-hidden="true"></span>新页面编辑
      </a>
      |
      <a href="/delete_teacher/?teacher_id={{ teacher.id }}" type="button" class="btn btn-sm btn-danger" aria-label="Left Align">
        <span class="glyphicon glyphicon-remove" aria-hidden="true"></span>删除
      </a>
    </td>
  </tr>
    {% empty %}
    <tr> <td colspan="3" style="text-align: center">空空如也~</td></tr>
  {% endfor %}
  </tbody>
</table>

删除老师信息

后端部分

后端从请求的URL中提取到要删除的老师的ID。

def delete_teacher(request):
    # 从GET请求的URL中取到要删除的老师ID
    teacher_id = request.GET.get("student_id")
    # 连接数据库
    conn = pymysql.connect(host="127.0.0.1", port=3306, user="root", passwd="root1234", db="mysite", charset="utf8")
    cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
    # 删除指定的老师
    sql = "delete from teacher WHERE id=%s;"
    # 执行SQL语句
    cursor.execute(sql, [teacher_id, ])
    conn.commit()
    conn.close()
    # 删除成功，跳转到老师列表页
    return redirect("/teacher_list/")

前端部分

点击页面上对应老师记录的删除按钮，向后端发送GET请求，将要删除的老师的ID传递给后端。

删除按钮部分HTML代码：

<a href="/delete_teacher/?teacher_id={{ class.id }}" type="button" class="btn btn-sm btn-danger" aria-label="Left Align">
  <span class="glyphicon glyphicon-remove" aria-hidden="true"></span>删除
</a>

新增老师信息

后端部分

这里我们对我们的数据库连接部分的代码做了优化。

from tools.sql_master import create, SQLManager
def add_teacher(request):
    if request.method == "POST":
        class_list = request.POST.getlist("class_id")
        teacher_name = request.POST.get("teacher_name")
        # 创建老师
        teacher_id = create("insert into teacher(name) VALUES (%s)", [teacher_name, ])
        # 更新teacher2class表
        # 多次链接，多次提交
        # for i in class_list:
        #     modify("insert into teacher2class(teacher_id, class_id) VALUES (%s, %s)", [teacher_id, i])
        #
        # # 一次链接，多次提交
        # db = SQLManager()
        # for i in class_list:
        #     db.moddify("insert into teacher2class(teacher_id, class_id) VALUES (%s, %s)", [teacher_id, i])
        # db.close()
        #
        # 一次链接，一次提交
        data_list = []
        for i in class_list:
            tmp = [teacher_id, i]
            data_list.append(tmp)
        db = SQLManager()
        db.multi_modify("insert into teacher2class(teacher_id, class_id) VALUES (%s, %s)", data_list)
        db.close()
        return redirect("/teacher_list/")
    else:
        class_list = get_list("select id, name from class")
        return render(request, "add_teacher.html", {"class_list": class_list})

前端部分

因为我们添加老师信息的时候，需要给老师指定关联的班级信息，所以在页面上需要将现有的班级信息展示出来。

新增老师信息时，输入老师的姓名然后选择关联的班级信息即可。

<form class="form-horizontal" action="/add_teacher/" method="post">
  <div class="form-group">
    <label for="inputclassname" class="col-sm-2 control-label">老师姓名</label>
    <div class="col-sm-10">
      <input type="text" class="form-control" name="teacher_name" id="inputclassname" placeholder="老师姓名">
    </div>
  </div>
  <div class="form-group">
    <label for="selectclass" class="col-sm-2 control-label">班级</label>
    <div class="col-sm-10">
      <select class="form-control" name="class_id" multiple>
        {% for class in class_list %}
          <option value="{{ class.id }}">{{ class.name }}</option>
        {% endfor %}
      </select>
    </div>
  </div>
  <div class="form-group">
    <div class="col-sm-offset-2 col-sm-10">
      <button type="submit" class="btn btn-default">提交</button>
    </div>
  </div>
</form>

编辑老师信息

后端部分

def edit_teacher(request):
    if request.method == "POST":
        teacher_id = request.POST.get("teacher_id")
        class_ids = request.POST.getlist("class_id")
        # 更新
        db = SQLManager()
        teacher_class_ids = db.get_list("select class_id from teacher2class WHERE teacher_id=%s", [teacher_id, ])
        old_class_ids = [i["class_id"] for i in teacher_class_ids]
        # 粗暴更新
        del_id_list = []
        add_id_list = []
        for i in old_class_ids:
            del_id_list.append((teacher_id, i))
        for j in class_ids:
            add_id_list.append((teacher_id, j))
        db.multi_modify("DELETE from teacher2class WHERE teacher_id=%s AND class_id=%s", del_id_list)
        db.multi_modify("insert into teacher2class(teacher_id, class_id) VALUES (%s, %s)", add_id_list)
        db.close()
        return redirect("/teacher_list")
    else:
        teacher_id = request.GET.get("teacher_id")
        with SQLManager() as db:
            class_list = db.get_list("select id, name from class")
            teacher_info = db.get_list("SELECT teacher.id, teacher.name, teacher2class.class_id FROM teacher  LEFT JOIN teacher2class ON teacher.id = teacher2class.teacher_id WHERE teacher.id=%s;", [teacher_id])
        ret = teacher_info[0]
        ret["class_ids"] = [ret["class_id"], ]
        for i in teacher_info[1:]:
            ret["class_ids"].append(i["class_id"])
        return render(request, "edit_teacher.html", {"class_list": class_list, "teacher": ret})

前端部分

<form class="form-horizontal" action="/edit_teacher/" method="post">
  <input type="text" name="teacher_id" value="{{ teacher.id }}" style="display: none">
  <div class="form-group">
    <label for="inputclassname" class="col-sm-2 control-label">学生姓名</label>
    <div class="col-sm-10">
      <input type="text" class="form-control" name="teacher_name" id="inputteachername" placeholder="老师姓名" value="{{ teacher.name }}">
    </div>
    <span id="helpBlock2" class="help-block">{{ error }}</span>
  </div>
  <div class="form-group">
      <label for="selectclass" class="col-sm-2 control-label">班级</label>
      <div class="col-sm-10">
        <select class="form-control" name="class_id" multiple>
          {% for class in class_list %}
            {% if class.id in teacher.class_ids %}
            <option selected value="{{ class.id }}">{{ class.name }}</option>
            {% else %}
            <option value="{{ class.id }}">{{ class.name }}</option>
            {% endif %}
          {% endfor %}
        </select>
      </div>
    </div>
  <div class="form-group">
    <div class="col-sm-offset-2 col-sm-10">
      <button type="submit" class="btn btn-default">提交</button>
    </div>
  </div>
</form>

可利用ORM实现模态框版增删改操作