Django：匹配的查询不存在

Question

在 DJango 中创建 ModelForm 实例时出错。 我并不总是面临这个问题，但有时它工作正常，有时它给我错误。

模型代码：

class ClientinfoForm(ModelForm):
    Account_Name = forms.CharField(disabled=True)
    class Meta:
        model = AccountDescription
        fields = ['Account_Name','short_Name','group_Master_Project_Code','account_Logo','vertical','client_Website','client_Revenue','Employee_Count','client_Industry_Segment','delivery_Manager_Mail','project_Manager_Mail']
        labels = {'client_Revenue':'Client Revenue(in USD Billion)','vertical':'Industry Vertical'}
        help_texts = {'client_revenue' : '(In Billion USD)' }   

views.py 代码

def save_client_info(request):
    fm = ClientinfoForm(request.POST, instance = AccountDescription.objects.get(Account_Name = acc_name),files = request.FILES or None)
    save_form(request,fm)


def clientinfo(request):
    if request.user.is_authenticated:
        if request.method == 'POST':
            print("inside form")
            save_client_info(request)
        global s4_option
        s4_option = AccountDescription.objects.filter(Account_Name = acc_name).values('s4_data')
        s4_option = s4_option[0]['s4_data']
        accdata = AccountDescription.objects.filter(Account_Name = acc_name)
        clientdata = ClientinfoForm(instance = AccountDescription.objects.get(Account_Name = acc_name))
        return render(request, 'AccountData/ClientInfo.html',{'name' : 'clientinfo','form':clientdata,'acntdata':accdata,'content':editoption})

有时，当我保存它时，它工作得很好，但有时它给出的匹配查询不存在。

如果需要更多信息，请告诉我。

Answer 1

换行

instance = AccountDescription.objects.get(Account_Name = acc_name)

在save_client_info 函数中类似于

from django.shortcuts import get_object_or_404

instance = get_object_or_404(AccountDescription, Account_Name=acc_name)

注意：我假设您已经在代码中的此行之前正确定义了acc_name。

因为总会有一些情况下这条记录不存在，而 Django 会引发does not exist 错误类型。或者，如果您的数据库中不存在此查询，您也可以返回所需的响应，例如：

from django.http import HttpResponse

try:
    fm = ClientinfoForm(request.POST, instance = AccountDescription.objects.get(Account_Name = acc_name),files = request.FILES or None)
except AccountDescription.DoesNotExist:
    return HttpResponse("Requested account does not exist") # or any other responses