在Django中添加ManyToMany

Question

我有一個web服務，我想將rdp配置文件添加到某個合同編號。

views.py

from django.shortcuts import render 
from program.models import contract,rdp 
from django.contrib.auth.decorators import login_required 

@login_required(login_url='login') 
def add_rdp(request): 
     if request.method == "POST": 

       get_rdp = (request.POST.get('rdp', '')) 
       get_number = (request.POST.get('contract_number','')) 

       new_rdp = rdp(config = get_rdp).save() 

       for new_contract in contract.objects.filter(number = get_number): 
         new_rdp.contract.add(new_contract) 

     return render(request, 'add_rdp.html') 

models.py

class contract(models.Model): 
     server = models.ForeignKey(server) 
     number = models.CharField(unique = True, max_length = 64) 

class rdp(models.Model): 
     contract = models.ForeignKey(contract) 
     config = models.TextField() 

這是錯誤我得到：

Integrity Error 
(1048, "Column 'contract_id' cannot be null") 

由於這種方法在其他Web應用程序在Django爲我工作，我無法弄清楚爲什麼這不起作用。

Answer 1

你必須得到模型實例，然後只需將其添加到您的「new_rdp」。你可以這樣做：

@login_required(login_url='login') 
def add_rdp(request): 
     if request.method == "POST": 

       get_rdp = (request.POST.get('rdp', '')) 
       get_number = (request.POST.get('contract_number','')) 

       for new_contract in contract.objects.all(): 
         if new_contract.number == get_number: 
           new_rdp = rdp(config = get_rdp, contract = new_contract).save() 

     return render(request, 'add_rdp.html') 

Answer 2

因爲您在沒有合同附加時致電save()。

你可以改變模型的定義：

class rdp(models.Model): 
     contract = models.ForeignKey(contract, blank = True) 
     config = models.TextField()