Django 表单和过滤

Question

所以我有这个作业选择表单，应该允许用户：

1）选择一组单选按钮的过滤器。这允许用户选择他想要过滤列表的方法。 （这将使用“filterBy”查询字符串 2 执行 GET

）允许用户通过来自 comobox 的对象（即 #1 的结果）过滤列表。此表单执行 POST，并将“filter”设置为 filterBy 对象的 pk

以下是我的代码：

selectForm = JobSelectForm()
filterByForm = FilterByForm()
filterForm = FilterForm()

if request.method == 'POST':
    #this works just fine
    if 'job' in request.POST:
        return HttpResponseRedirect("/portal/jobs/%s/"%(request.POST['job']))

    if 'filter' in request.POST:
        filterForm = FilterForm(initial = {'filter': request.POST['filter']})

        ###### The Problem is below here
        ###### I cant get the 'filterBy' query string 
        ###### because this is a POST and not a GET
        ###### Is there a better way to write this filtering?

        if request.GET['filterby'] == 'G':
            obj = Group.objects.get(pk=request.POST['filter'])
            selectForm.fields['job'].queryset = Job.objects.filter(group=obj).order_by('name')
        elif request.GET['filterby'] == 'H':
            obj = Host.objects.get(pk=request.POST['filter'])
            selectForm.fields['job'].queryset = Job.objects.filter(host=obj).order_by('name')
        elif request.GET['filterby'] == 'L':
            obj = Location.objects.get(pk=request.POST['filter'])
            selectForm.fields['job'].queryset = Job.objects.filter(colo=obj).order_by('name')

###### All of this works fine too
elif request.method == 'GET':
    if request.GET.has_key('filterby'):
        if request.GET['filterby']:
            filterByForm = FilterByForm(initial = {'filterby': request.GET['filterby']})
            if request.GET['filterby'] == 'G':
                filterForm.fields['filter'].queryset = Group.objects.all().order_by('name')
            elif request.GET['filterby'] == 'H':
                filterForm.fields['filter'].queryset = Host.objects.all().order_by('name')
            elif request.GET['filterby'] == 'L':
                filterForm.fields['filter'].queryset = Location.objects.all().order_by('name')

Answer 1

使用 request.REQUEST （请参阅：Django 请求和响应对象）。它包含 request.POST 和 request.GET 的值。

另外，在 Python 中使用字典时，您应该始终验证您尝试访问的密钥是否存在。这可以通过以下两种方式之一完成：

1) 显式测试字典中的键

if request.GET.has_key('filterby') and request.GET['filterby'] == 'G':
    obj = Group.objects.get(pk=request.POST['filter'])
    selectForm.fields['job'].queryset = Job.objects.filter(group=obj).order_by('name')

2) 使用字典的 get 方法

if request.GET.get('filterby') == 'G':
    obj = Group.objects.get(pk=request.POST['filter'])
    selectForm.fields['job'].queryset = Job.objects.filter(group=obj).order_by('name')

使用 dict.get 您还可以传递默认值:

if request.GET.get('filterby', valueIfKeyDoesntExist) == 'G':
    obj = Group.objects.get(pk=request.POST['filter'])
    selectForm.fields['job'].queryset = Job.objects.filter(group=obj).order_by('name')

Answer 2

您应该将有问题的代码放在表单的重写 __init__ 方法中。