第三百七十四节，Django+Xadmin打造上线标准的在线教育平台—创建课程app，在models.py文件生成4张表，课程表、课程章节表、课程视频表、课程资源表

第三百七十四节，Django+Xadmin打造上线标准的在线教育平台—创建课程app，在models.py文件生成4张表，课程表、课程章节表、课程视频表、课程资源表

创建名称为app_courses的课程APP，写数据库操作文件models.py

models.py文件

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from __future__ import unicode_literals
from datetime import datetime

from django.db import models        # 导入models对象

class Course(models.Model):
    name = models.CharField(max_length=50, verbose_name='课程名称')
    desc = models.CharField(max_length=300, verbose_name='课程描述')
    detail = models.TextField(verbose_name='课程详情')
    degree = models.CharField(verbose_name='课程级别', choices=(('cj', '初级'), ('zj', '中级'), ('gj', '高级')), max_length=3)
    learn_times = models.IntegerField(default=0, verbose_name='学习时长(分钟)')
    students = models.IntegerField(default=0, verbose_name='学习人数')
    fav_nums = models.IntegerField(default=0, verbose_name='收藏人数')
    image = models.ImageField(upload_to='courses/%Y/%m', verbose_name='课程封面图', max_length=100)
    click_nums = models.IntegerField(default=0, verbose_name='点击数')
    add_time = models.DateTimeField(default=datetime.now, verbose_name='添加时间')

    class Meta:
        verbose_name = '课程表'
        verbose_name_plural = verbose_name

class Lesson(models.Model):
    course = models.ForeignKey(Course, verbose_name='外键课程表')      # 外键链表，外键连接Course表的主键，一对多关系
    name = models.CharField(max_length=100, verbose_name='章节名')
    add_time = models.DateTimeField(default=datetime.now, verbose_name='添加日期')

    class Meta:
        verbose_name = '课程章节表'
        verbose_name_plural = verbose_name

class Video(models.Model):
    lesson = models.ForeignKey(Lesson, verbose_name='外键章节表')
    name = models.CharField(max_length=100, verbose_name='视频名')
    add_time = models.DateTimeField(default=datetime.now, verbose_name='添加日期')

    class Meta:
        verbose_name = '课程视频表'
        verbose_name_plural = verbose_name

class CourseResource(models.Model):
    course = models.ForeignKey(Course, verbose_name='外键课程表')
    name = models.CharField(max_length=100, verbose_name='课程资源名称')
    download = models.FileField(upload_to='course/resource/%Y/%m', verbose_name='资源文件', max_length=100)
    add_time = models.DateTimeField(default=datetime.now, verbose_name='添加日期')

    class Meta:
        verbose_name = '课程资源表'
        verbose_name_plural = verbose_name