Django 将来自外部模型的条目设置为可选

我有以下型号。py：

class trainee(models.Model):
        username = models.TextField(verbose_name = 'username')

class learningObjective(models.Model):
        trainee = models.ForeignKey(trainee, verbose_name = "Azubi")
        learningObjectives = models.TextField(verbose_name = 'Lernziel')

class completedTask(models.Model):
        trainee = models.ForeignKey(trainee, verbose_name = "Azubi")
        learningObjectivecompletedTask = models.ManyToManyField(learningObjective, verbose_name = "Lernziel")
        date = models.DateField(verbose_name = 'Datum')
        duration = models.IntegerField(verbose_name = 'Dauer')
        documentationReference = models.TextField(verbose_name = 'Dokumentationsverweis', blank = True)
        educationDepartment = models.TextField(verbose_name = 'Ausbildungsabteilung')
        completedtasks = models.TextField(verbose_name = 'Ausgefuehrte Taetigkeiten')

@login_required(login_url='login')
def create_at(request):
        trainee_objects = trainee.objects.all()
        usernameID = 1
        for traineeUser in trainee_objects:
                if traineeUser.username == request.user.username:
                        usernameID = traineeUser.id
        if request.method == 'POST':
                form = completedTaskForm(request.POST)
                if form.is_valid():
                        neueAT=completedTask(date=request.POST['Datum'], duration=request.POST['Dauer'], educationDepartment=request.POST['Abteilung'], completedtasks=request.POST['AT'], trainee_id=usernameID)
                        neueAT.save()
                        for ct in learningObjective.objects.filter(learningObjectives=request.POST.get['Lernziel']):
                                 neueAT.learningObjectivecompletedTask.add(ct)
                 else:
                        form = completedTask()
         return render(request, 'at.html', {'at': completedTask.objects.all(), 'Lernziel': learningObjective.objects.all()})

trainee_objects = trainee.objects.all()
        usernameID = 1
        for traineeUser in trainee_objects:
                if traineeUser.username == request.user.username:
                        usernameID = traineeUser.id

        if request.method == 'POST':
                forms = completedTaskForm(request.POST)
                if forms.is_valid():
                        formlearningObjectives = forms.cleaned_data['formlearningObjectives']
                        formdate = forms.cleaned_data['formdate']
                        formduration = forms.cleaned_data['formduration']
                        formeducationDepartment = forms.cleaned_data['formeducationDepartment']
                        formcompletedtasks = forms.cleaned_data['formcompletedtasks']

                        neueAT=completedTask(date=formdate, duration=formduration, educationDepartment=formeducationDepartment, completedtasks=formcompletedtasks, trainee_id=usernameID)
                        neueAT.save()
                        for ct in learningObjective.objects.filter(learningObjectives=formlearningObjectives):
                                neueAT.learningObjectivecompletedTask.add(ct)
                else:
                        form = completedTask()
                        print("Es hat fehlgeschlagen!" + formset.errors)
        return render(request, 'at.html', {'at': completedTask.objects.all(), 'Lernziel': learningObjective.objects.all()})

这是我的视图的一部分。py：

class trainee(models.Model):
        username = models.TextField(verbose_name = 'username')

class learningObjective(models.Model):
        trainee = models.ForeignKey(trainee, verbose_name = "Azubi")
        learningObjectives = models.TextField(verbose_name = 'Lernziel')

class completedTask(models.Model):
        trainee = models.ForeignKey(trainee, verbose_name = "Azubi")
        learningObjectivecompletedTask = models.ManyToManyField(learningObjective, verbose_name = "Lernziel")
        date = models.DateField(verbose_name = 'Datum')
        duration = models.IntegerField(verbose_name = 'Dauer')
        documentationReference = models.TextField(verbose_name = 'Dokumentationsverweis', blank = True)
        educationDepartment = models.TextField(verbose_name = 'Ausbildungsabteilung')
        completedtasks = models.TextField(verbose_name = 'Ausgefuehrte Taetigkeiten')

@login_required(login_url='login')
def create_at(request):
        trainee_objects = trainee.objects.all()
        usernameID = 1
        for traineeUser in trainee_objects:
                if traineeUser.username == request.user.username:
                        usernameID = traineeUser.id
        if request.method == 'POST':
                form = completedTaskForm(request.POST)
                if form.is_valid():
                        neueAT=completedTask(date=request.POST['Datum'], duration=request.POST['Dauer'], educationDepartment=request.POST['Abteilung'], completedtasks=request.POST['AT'], trainee_id=usernameID)
                        neueAT.save()
                        for ct in learningObjective.objects.filter(learningObjectives=request.POST.get['Lernziel']):
                                 neueAT.learningObjectivecompletedTask.add(ct)
                 else:
                        form = completedTask()
         return render(request, 'at.html', {'at': completedTask.objects.all(), 'Lernziel': learningObjective.objects.all()})

trainee_objects = trainee.objects.all()
        usernameID = 1
        for traineeUser in trainee_objects:
                if traineeUser.username == request.user.username:
                        usernameID = traineeUser.id

        if request.method == 'POST':
                forms = completedTaskForm(request.POST)
                if forms.is_valid():
                        formlearningObjectives = forms.cleaned_data['formlearningObjectives']
                        formdate = forms.cleaned_data['formdate']
                        formduration = forms.cleaned_data['formduration']
                        formeducationDepartment = forms.cleaned_data['formeducationDepartment']
                        formcompletedtasks = forms.cleaned_data['formcompletedtasks']

                        neueAT=completedTask(date=formdate, duration=formduration, educationDepartment=formeducationDepartment, completedtasks=formcompletedtasks, trainee_id=usernameID)
                        neueAT.save()
                        for ct in learningObjective.objects.filter(learningObjectives=formlearningObjectives):
                                neueAT.learningObjectivecompletedTask.add(ct)
                else:
                        form = completedTask()
                        print("Es hat fehlgeschlagen!" + formset.errors)
        return render(request, 'at.html', {'at': completedTask.objects.all(), 'Lernziel': learningObjective.objects.all()})

因此，我现在有一个字段，我必须为模型completedTask填充该字段。除非有人没有填写实际需要的数据，否则一切正常。我正在写一个应用程序来记录你在工作时间所做的事情，当然你应该立即正确地输入所有内容。但是如果不能立即创建一个条目，则不应该抛出错误。如何使多个字段成为可选字段。我认为我可以简单地创建一个默认值，当用户更新其条目时，该值会被删除。但我不想那样做。在我的数据库中有一个空白条目会很酷，现在就是这样。但当我这样做时，它会给我以下错误：

在/program/create_处出现多值错误

它创建了条目和所有内容，这些都很好，但我想消除错误。是否有一个模板标记，用于检查字段是否有输入？我试图寻找它，但没有成功。如果你需要更多的信息，请告诉我

编辑：（这些是我的表单，第一次使用它们）

没有任何条目了。

打印（form.error）

的输出如下：

日期

本周 字段为必填项。

持续时间

此字段为必填项。

completedtasks

此字段为 必选。

教育部

此字段为必选。

---

请引导我，我现在很困。

哇，我为自己感到骄傲：p解决方案是表单

from django import forms
from programm.models import trainee, todoList, learningObjective, topic, person, completedTask, remark

class completedTaskForm(forms.Form):
        trainee = forms.IntegerField(required = True)
        learningObjectivecompletedTask = forms.CharField(required = False)
        date = forms.DateField(required = True)
        duration = forms.IntegerField(required = True)
        documentationReference = forms.CharField(required = False)
        educationDepartment = forms.CharField(required = True)
        completedtasks = forms.CharField(required = True)

在我的视图中进行此编辑：

class trainee(models.Model):
        username = models.TextField(verbose_name = 'username')

class learningObjective(models.Model):
        trainee = models.ForeignKey(trainee, verbose_name = "Azubi")
        learningObjectives = models.TextField(verbose_name = 'Lernziel')

class completedTask(models.Model):
        trainee = models.ForeignKey(trainee, verbose_name = "Azubi")
        learningObjectivecompletedTask = models.ManyToManyField(learningObjective, verbose_name = "Lernziel")
        date = models.DateField(verbose_name = 'Datum')
        duration = models.IntegerField(verbose_name = 'Dauer')
        documentationReference = models.TextField(verbose_name = 'Dokumentationsverweis', blank = True)
        educationDepartment = models.TextField(verbose_name = 'Ausbildungsabteilung')
        completedtasks = models.TextField(verbose_name = 'Ausgefuehrte Taetigkeiten')

@login_required(login_url='login')
def create_at(request):
        trainee_objects = trainee.objects.all()
        usernameID = 1
        for traineeUser in trainee_objects:
                if traineeUser.username == request.user.username:
                        usernameID = traineeUser.id
        if request.method == 'POST':
                form = completedTaskForm(request.POST)
                if form.is_valid():
                        neueAT=completedTask(date=request.POST['Datum'], duration=request.POST['Dauer'], educationDepartment=request.POST['Abteilung'], completedtasks=request.POST['AT'], trainee_id=usernameID)
                        neueAT.save()
                        for ct in learningObjective.objects.filter(learningObjectives=request.POST.get['Lernziel']):
                                 neueAT.learningObjectivecompletedTask.add(ct)
                 else:
                        form = completedTask()
         return render(request, 'at.html', {'at': completedTask.objects.all(), 'Lernziel': learningObjective.objects.all()})

trainee_objects = trainee.objects.all()
        usernameID = 1
        for traineeUser in trainee_objects:
                if traineeUser.username == request.user.username:
                        usernameID = traineeUser.id

        if request.method == 'POST':
                forms = completedTaskForm(request.POST)
                if forms.is_valid():
                        formlearningObjectives = forms.cleaned_data['formlearningObjectives']
                        formdate = forms.cleaned_data['formdate']
                        formduration = forms.cleaned_data['formduration']
                        formeducationDepartment = forms.cleaned_data['formeducationDepartment']
                        formcompletedtasks = forms.cleaned_data['formcompletedtasks']

                        neueAT=completedTask(date=formdate, duration=formduration, educationDepartment=formeducationDepartment, completedtasks=formcompletedtasks, trainee_id=usernameID)
                        neueAT.save()
                        for ct in learningObjective.objects.filter(learningObjectives=formlearningObjectives):
                                neueAT.learningObjectivecompletedTask.add(ct)
                else:
                        form = completedTask()
                        print("Es hat fehlgeschlagen!" + formset.errors)
        return render(request, 'at.html', {'at': completedTask.objects.all(), 'Lernziel': learningObjective.objects.all()})

---

看看这里的表单：这和我两个小时以来做的事情完全一样。我太迟钝了，不能想出解决问题的办法：P我正在努力^^