Django创建并连接数据库（实现增删改查）--第二版
注意点一：
url里面的地址，不只是html页面，准确说是views视图里面对应的函数方法
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css"> <title>出版社列表</title> </head> <body> <div class="container"> <div class="row"> <div class="col-md-6 col-md-offset-3"> <h2>出版社列表</h2> <table class="table table-condensed"> <thead> <tr> <th>ID</th> <th>出版社名称</th> <th>出版社地址</th> <th>邮箱</th> <th>操作</th> </tr> </thead> <tbody> {% for publish in publish_list %} <tr> <td>{{ forloop.counter }}</td> <td>{{ publish.name}}</td> <td>{{ publish.addr }}</td> <td>{{ publish.email }}</td> <td> <!--定义2个链接，点击之后实质是向服务端又提交了一个get请求，并且把对应那天数据的nid发送给服务端--> <!--get方式携带参数到后台，例如？nid=123&name=yzz(后面可以跟多个)，但是nid是唯一的，所以用nid--> <!--会触发视图里面的删除方法，将要删除数据的nid当做参数传入--> <a href="/delete_publish/?nid={{ publish.nid }}" class="btn btn-danger">删除</a> <a href="/edit_publish/?nid={{ publish.nid }}" class="btn btn-success">编辑</a> </td> </tr> {% endfor %} </tbody> </table> </div> </div> </div> </body> </html>
注意点二：
1.views.py里面配置的视图函数
2.注意get带参数的请求与post请求
3.多对多产生第三张表的方法，已经默认建好之后表的名字和字段的名字
from django.shortcuts import render,HttpResponse,redirect # Create your views here. from app01.models import * #添加出版社 def add_publish(request): if request.method=='POST': name = request.POST.get('name') addr = request.POST.get('addr') email = request.POST.get('email') Publish.objects.create(name=name,addr=addr,email=email) #点击添加后信息重定向到查看出版社列表的方法界面 return redirect('/publish_list/') #跳转到查看界面，可以完成编辑和删除操作 #如果是get请求默认就是添加出版社界面 return render(request,"add_publish.html") #查看出版社信息 def publish_list(request): publish_list=Publish.objects.all() return render(request,'publish_list.html',{'publish_list':publish_list}) #删除出版社信息 def delete_publish(request): nid=request.GET.get('nid') print(nid) #是实际数据库里面的id值（不是{ forloop.counter }}页面上看到的设定的自动增长的值） # 通过filter过滤出nid为传入的nid，删除掉 #filter功能相当与：select * from where id =2; ret=Publish.objects.filter(nid=nid) #ret是个列表 # 删除这些数据 print(ret) #<QuerySet [<Publish: Publish object>]> ret.delete() return redirect('/publish_list/') #编辑出版社信息 def edit_publish(request): # post请求：是编辑完之后提交数据的请求 if request.method=='POST': nid=request.POST.get('nid') name=request.POST.get('name') addr=request.POST.get('addr') email=request.POST.get('email') #先查找，再更新 Publish.objects.filter(pk=nid).update(name=name, addr=addr, email=email) return redirect('/publish_list/') #Get请求：数据拿过来跳转到编辑页面 nid=request.GET.get('nid') #Publish.objects.filter(nid=nid) 是个列表,类表的第一个值是对象 # aa=Publish.objects.filter(nid=nid) # print(aa.__dict__) #{'model': <class 'app01.models.Publish'>, '_db': None, '_hints': {},..} publish=Publish.objects.filter(nid=nid).first() #publish是个对象 print(publish) return render(request,'edit_publish.html',{'publish':publish}) #添加书名信息 def add_book(request): if request.method=='POST': name=request.POST.get('name') price=request.POST.get('price') pub_date=request.POST.get('pub_date') #添加表示出版社的id字段 publish_id=request.POST.get('publish') #拿到对应的作者的列表，authors是个对象，传递的是每个对象对应的id号 authors=request.POST.getlist('authors') #authors是个列表 book=Book.objects.create(name=name,price=price,pub_date=pub_date,publish_id=publish_id) #会在书与作者多对多关系产生的第三张表book_authors里面添加表记录 book.authors.add(*authors) #把每个作者的类表id打乱传入 return redirect('/book_list/') #默认拿到出版社列表、作者列表 publish_list = Publish.objects.all() author_list = Author.objects.all() return render(request,'add_book.html',{'publish_list':publish_list,'author_list':author_list}) def book_list(request): book_list=Book.objects.all() return render(request,'book_list.html',{'book_list':book_list}) def delete_book(request): nid = request.GET.get('nid') ret = Book.objects.filter(nid=nid) # ret是个列表 ret.delete() return redirect('/book_list/') def edit_book(request): if request.method=='POST': nid=request.POST.get('nid') name=request.POST.get('name') price=request.POST.get('price') pub_date=request.POST.get('pub_date') publish_id=request.POST.get('publish') authors=request.POST.getlist('authors') Book.objects.filter(pk=nid).update(name=name,price=price,pub_date=pub_date,publish_id=publish_id) book=Book.objects.filter(pk=nid).first() #重置authors的值（用于更新到第三张表里面）,先删除原纪录再添加 book.authors.set(authors) #相当于 # book.authors.clear() # book.authors.add(*authors) return redirect('/book_list/') nid = request.GET.get('nid') book=Book.objects.filter(nid=nid).first() publish_list=Publish.objects.all() author_list=Author.objects.all() return render(request,'edit_book.html',{'book':book,'publish_list':publish_list,'author_list':author_list})
from django.db import models # Create your models here. #出版社数据库指定的字段及类型 class Publish(models.Model): nid=models.AutoField(primary_key=True) name=models.CharField(max_length=32) addr=models.CharField(max_length=64) # 也是varchar类型 email=models.EmailField() #作者数据中指定的字段及类型 class Author(models.Model): nid = models.AutoField(primary_key=True) name=models.CharField(max_length=32) age=models.IntegerField() #图书数据库指定的字段及类型 class Book(models.Model): nid = models.AutoField(primary_key=True) name=models.CharField(max_length=32) price=models.DecimalField(max_digits=5,decimal_places=2) pub_date=models.DateField() #建立书与出版社一对多关系 # to后面的那个表，可以不加引号，但是，要在前面定义（即Publish类要写在Book的前面） publish=models.ForeignKey(to='Publish',to_field='nid') #创建完成表字段会是 publish_id #建立书与作者多对多关系 #作用：针对对对多关系，创建建爱你出第三张表（代替了下面的3行代码） authors=models.ManyToManyField(to='Author') #这是第三张表的名字：book_authors,包含的字段有book_id author_id # class Book2Author(models.Model): # nid=models.AutoField(primary_key=True) # book=models.ForeignKey(to='Book',to_field='nid') # author=models.ForeignKey(to='Author',to_field='nid')
注意点三：templates模本文件下面的一些配置文件
1.注意页面格式的书写
2.注意里面for循环的一个取值
3.get方法传参的应用
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>新增图书</title> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css"> </head> <body> <div class="container"> <div class="row"> <div class="col-md-6 col-md-offset-3"> <h2>新增图书</h2> <form action="/add_book/" method="post"> <input type="hidden" name="nid" class="form-control" value="{{ publish.nid }}"> <p>图书名称：<input type="text" name="name" class="form-control"></p> <p>价格：<input type="text" name="price" class="form-control" ></p> <p>出版日期：<input type="date" name="pub_date" class="form-control"></p> <p>出版社： <!--循环出出版社列表，让那个让用户进行出版社名字，对应提交的就是对应出版社的id--> <select name="publish" id="" class="form-control"> {% for publish in publish_list %} <option value="{{ publish.nid }}">{{ publish.name }}</option> {% endfor %} </select> </p> <p>作者： <select name="authors" id="" multiple class="form-control"> {% for author in author_list %} <option value="{{ author.nid }}">{{ author.name }}</option> {% endfor %} </select> </p> <p><input type="submit" value="提交" class="form-control btn btn-success"></p> </form> </div> </div> </div> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>图书列表</title> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css"> </head> <body> <div class="container"> <div class="row"> <div class="col-md-6 col-md-offset-3"> <h2>图书列表</h2> <table class="table table-condensed"> <thead> <tr> <th>ID</th> <th>书名</th> <th>价格</th> <th>出版日期</th> <th>出版社名称</th> <th>作者</th> <th>操作</th> </tr> </thead> <tbody> {% for book in book_list %} <tr> <td>{{ forloop.counter }}</td> <td>{{ book.name}}</td> <td>{{ book.price }}</td> <td>{{ book.pub_date|date:'Y-m-d' }}</td> <td>{{ book.publish.name }}</td> <td> {% for author in book.authors.all %} {{ author.name }}| {% endfor %} </td> <td> <a href="/delete_book/?nid={{ book.nid }}" class="btn btn-danger">删除</a> <a href="/edit_book/?nid={{ book.nid }}" class="btn btn-success">编辑</a> </td> </tr> {% endfor %} </tbody> </table> </div> </div> </div> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>编辑图书</title> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css"> </head> <body> <div class="container"> <div class="row"> <div class="col-md-6 col-md-offset-3"> <h2>新增图书</h2> <form action="/edit_book/" method="post"> <input type="hidden" name="nid" value="{{ book.nid }}"> <p>图书名称：<input type="text" name="name" class="form-control" value="{{ book.name }}"></p> <p>价格：<input type="text" name="price" class="form-control" value="{{ book.price }}"></p> <p>出版日期：<input type="date" name="pub_date" class="form-control" value="{{ book.pub_date|date:"Y-m-d" }}"></p> <p>出版社： <select name="publish" id="" class="form-control"> <!--判断，编辑时让编辑状态下图书对应的出版社默认就是后台对应的--> {% for publish in publish_list %} {% if book.publish == publish %} <option selected value="{{ publish.nid }}">{{ publish.name }}</option> {% else %} <option value="{{ publish.nid }}">{{ publish.name }}</option> {% endif %} {% endfor %} </select> </p> <p>作者： <select name="authors" id="" multiple class="form-control"> <!--判断，编辑时让作者一栏和初始状态的书对应--> {% for author in author_list %} {% if author in book.authors.all %} <option selected value="{{ author.nid }}">{{ author.name }}</option> {% else %} <option value="{{ author.nid }}">{{ author.name }}</option> {% endif %} {% endfor %} </select> </p> <p><input type="submit" value="提交" class="form-control btn btn-success"></p> </form> </div> </div> </div> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>新增出版社</title> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css"> </head> <body> <div class="container"> <div class="row"> <div class="col-md-6 col-md-offset-3"> <h2>添加出版社</h2> <form action="/add_publish/" method="post"> <p>出版社名称：<input type="text" name="name" class="form-control"></p> <p>出版社地址：<input type="text" name="addr" class="form-control"></p> <p>出版社邮箱：<input type="text" name="email" class="form-control"></p> <p><input type="submit" value="添加" class="form-control btn btn-success"></p> </form> </div> </div> </div> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css"> <title>出版社列表</title> </head> <body> <div class="container"> <div class="row"> <div class="col-md-6 col-md-offset-3"> <h2>出版社列表</h2> <table class="table table-condensed"> <thead> <tr> <th>ID</th> <th>出版社名称</th> <th>出版社地址</th> <th>邮箱</th> <th>操作</th> </tr> </thead> <tbody> {% for publish in publish_list %} <tr> <td>{{ forloop.counter }}</td> <td>{{ publish.name}}</td> <td>{{ publish.addr }}</td> <td>{{ publish.email }}</td> <td> <!--定义2个链接，点击之后实质是向服务端又提交了一个get请求，并且把对应那天数据的nid发送给服务端--> <!--get方式携带参数到后台，例如？nid=123&name=yzz(后面可以跟多个)，但是nid是唯一的，所以用nid--> <!--会触发视图里面的删除方法，将要删除数据的nid当做参数传入--> <a href="/delete_publish/?nid={{ publish.nid }}" class="btn btn-danger">删除</a> <a href="/edit_publish/?nid={{ publish.nid }}" class="btn btn-success">编辑</a> </td> </tr> {% endfor %} </tbody> </table> </div> </div> </div> </body> </html>
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>修改出版社</title> <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css"> </head> <body> <div class="container"> <div class="row"> <div class="col-md-6 col-md-offset-3"> <h2>修改出版社</h2> <form action="/edit_publish/" method="post"> <!--{{ publish.nid }}:点击编辑时默认显示原来数据，在基础上进行修改--> <input type="hidden" name="nid" class="form-control" value="{{ publish.nid }}"> <p>出版社名称：<input type="text" name="name" class="form-control" value="{{ publish.name }}"></p> <p>出版社地址：<input type="text" name="addr" class="form-control" value="{{ publish.addr }}"></p> <p>出版社邮箱：<input type="text" name="email" class="form-control" value="{{ publish.email }}"></p> <p><input type="submit" value="修改" class="form-control btn btn-success"></p> </form> </div> </div> </div> </body> </html>
