Django Can't save form data on database - django

Question

I'm trying write a small app while I'm learning django.However, when I try to save the form data in database, some problems happen to me.I use python3.4 and django 1.8.4, my database is MySql
The first problem I met is that the database doesn't have any data
this is my model code:
SUBJECT_CHOICES = (
('computerscience', '计算机科学导论'),
('C-sharp', 'C#'),
('cplusplus', 'C++'),
('CCNA', 'CCNA'),
('ACM', 'ACM'),
('linux', 'linux'),
('java', 'java'),
('python', 'python')
)
class Homework(models.Model):
handin_date = models.DateTimeField('交作业时间')
subject = models.CharField(verbose_name = '课程', default = '计算机科学导论', max_length = 20, choices = SUBJECT_CHOICES)
code = models.TextField(verbose_name = '代码', default = '')
xuehao = models.CharField(verbose_name = '学号', default = '', max_length = 9)
name = models.CharField(verbose_name = '姓名', default = '', max_length = 10)
this is my view code:
def cshomework(request):
if request.method == 'POST':
form = HomeworkForm(request.POST)
if form.is_valid():
return render(request, 'blog/success.html', { 'title': '交作业成功' })
else:
form = HomeworkForm(initial = { 'xuehao': '学号', 'name': '姓名', 'subject': '计算机科学导论', 'handin_date': dt.now(), 'code': '你的代码' })
return render(request, 'blog/cshomework.html', { 'title': '交作业', 'form': form })
In this way there's nothing in my database
The seconde question is when I tried another way, I get a None value in my datebase
The same model code as before
Here is my view code:
def cshomework(request):
if request.method == 'POST':
form = HomeworkForm(request.POST)
if form.is_valid():
return render(request, 'blog/success.html', { 'title': '交作业成功' })
else:
homework = Homework.objects.create(xuehao = '学号', name = '姓名', subject = '计算机科学导论', handin_date = dt.now(), code = '你的代码')
form = HomeworkForm(instance = homework)
return render(request, 'blog/cshomework.html', { 'title': '交作业', 'form': form })
the '课程' means 'subject'
How can I deal with these problems?
I' really appriciate your help!

Answer 1

After all check if form.is_valid(), you need save the form.
def cshomework(request):
if request.method == 'POST':
form = HomeworkForm(request.POST)
if form.is_valid():
form.save()
return render(request, 'blog/success.html', { 'title': '交作业成功' })
else:
form = HomeworkForm(initial = { 'xuehao': '学号', 'name': '姓名', 'subject': '计算机科学导论', 'handin_date': dt.now(), 'code': '你的代码' })
return render(request, 'blog/cshomework.html', { 'title': '交作业', 'form': form })
At the second way, you are creating a new HomeWork everytime a URL is accessed, without submit any post data.