• Django框架图书管理系统编辑界面的实现


    from django.shortcuts import render,HttpResponse,redirect
    from book.models import Book
    from django.urls import reverse
    import datetime
    # Create your views here.
    def add_book(request):

    if request.method == "GET":
    return render(request, "add_book.html")
    else:
    #方式一
    #title =request.POST.get("title")
    #price = request.POST.get("price")
    #pub_date = request.POST.get("pub_date")
    #Book.objects.create(title=title,price=price,pub_date=pub_date)
    #方式二
    #request.POST.dict()
    Book.objects.create(**request.POST.dict())

    path = reverse("app01_book")
    return redirect(path)
    #return HttpResponse("添加书籍")


    #添加书籍
    # 方式1
    #date = datetime.date(year=2012,month=12,day=12)
    #book = Book(title="xiyouji", price=199, pub_date=date)
    book = Book(title="xiyouji",price=199,pub_date="2012-12-12")
    print(book.id) #None
    book.save() #执行sql
    print(book.id) # 3

    # 方式2
    book = Book.objects.create(title="sanguoyanyi",price=299,pub_date="2011-11-11")
    print(book.id)
    print(book.price)

    def select_book(request):

    #return render(request,"add_book.html")
    # (1) 查询所有的书籍,返回值是一个queryset类型对象
    book_list= Book.objects.all()
    '''
    ORM数据引擎:

    select id, title, price, pub_date from book:
    +------+--------------+---------+------------+
    id title price pub_date
    +------+--------------+---------+------------+
    1 西游记 499.00 2011-12-12
    2 三国演义 399.00 2019-06-12
    3 水浒传 299.00 2008-06-12
    4 红楼梦 199.00 2020-06-12
    +------+--------------+---------+------------+
    book01 = Book(1 | 西游记 |499.00 |2011-12-12)
    book02 = Book(2 | 三国演义 |399.00 |2019-06-12)
    book03 = Book(3 | 水浒传 |299.00 |2008-06-12)
    book04 = Book(4 | 红楼梦 |199.00 |2020-06-12)

    book_list = queryset[book01,book02,book03,book04]

    '''
    #print ("book_list",book_list) # <QuerySet [<Book: Book object (1)>,...]

    #QuerySet:支持索引操作,支持遍历
    #book = book_list[0]
    #print(book.id) # 1
    #print(book.title) # 西游记
    #print(book.price) # 499.00
    # print(book_list.title)
    #for book in book_list:
    #print (book.id,book.title) #1 西游记 2 三国演义 3 水浒传 4 红楼梦

    #return HttpResponse("添加书籍")

    # (2) filter方法: 返回queryset
    book_list = Book.objects.filter(price=455) #查看价格为455.00的书籍信息

    # (3) exclude方法:排除符合条件的返回queryset类型对象
    book_list = Book.objects.exclude(price=455) #排除价格等于455.00的书籍信息

    # (4) get方法: 返回值模型类对象 特点: 查询有且只有一个对象时正常返回
    book = Book.objects.get(id=7) #查看id为7的书籍信息(唯一一条)
    print("book",book)
    print("book", book.title,book.price) ##查看id为7的书籍信息的书籍名称和价格(唯一一条)

    # (5) first方法,last方法
    book = Book.objects.first() # 查询第一条书籍信息
    book = Book.objects.last() # 查询最后一条书籍信息
    print(book.title)

    # (6) queryset.orderby方法:
    book_list = Book.objects.all().order_by("-price") # 按价格排除
    book_list = Book.objects.all().filter(price_gt=300).order_by("-price") #查询价格大于300.00,并排序

    # (7) queryset.count() 计数:
    n = book = Book.objects.count()
    print (n) # 9

    # (8) value(列表.字典),value_list(列表.元组)
    #value(列表.字典)
    book_list = Book.objects.values("title","price","pub_date")
    book_list = Book.objects.filter(price=455).values("title","price","pub_date")
    print("book_list", book_list)
    #value_list(列表.元组)
    book_list2 = Book.objects.filter(price=455).values("title","price","pub_date")
    print("book_list2", book_list2)

    return render(request,"books.html",{"book_list":book_list})



    def update_book(request):
    # 方式1:
    book = Book.objects.get(pk=7) #更新id等于7的书籍名为菜根谭3
    book.title = "菜根谭3"
    print(book.title)
    book.save() # updaate set

    # 方式2:

    Book.objects.filter(pk=7).update(title="菜根谭3") #更新id等于7的书籍名为菜根谭3
    return HttpResponse("OK")

    def delete_book(request,del_id):
    if request.method == "GET":
    return render(request,"delete_book.html")



    # 方式1:
    #book = Book.objects.get(pk=7) #删除id等于7的书籍信息
    #book.delete()

    # 方式2:
    #book_list = Book.objects.filter(price=1199) #删除价格等于1199.00的书籍信息
    #book_list.delete()
    Book.objects.get(pk=del_id).delete()
    return redirect("/book/")


    def edit_book(request,edit_id):
    if request.method =="GET":
    edit_book = Book.objects.get(id=edit_id)
    return render(request,"edit_book.html",{"edit_book":edit_book})
    else:
    data = request.POST.dict()
    Book.objects.filter(id=edit_id).update(**data)
    return redirect("/book/")
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  • 原文地址:https://www.cnblogs.com/A121/p/16515388.html
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