Question

DJANGO / PYTHON 我正在尝试加载http://127.0.0.1:8000/catalog/。如果用户在此页面上输入数据，则表单会将search_query发送到数据库。我的问题是http://127.0.0.1:8000/catalog/无法加载-它导致异常值'search_query'的'MultiValueDictKeyError'异常类型。但是，当用户将数据提交到表单中时（即http://127.0.0.1:8000/catalog/?search_query=biography+of），页面就会加载。我正在尝试使http://127.0.0.1:8000/catalog/加载而用户不必提交搜索查询。

这是我的查看功能：

def index(request):
   . . .
     num_of_word = []
     bookInstance_titles = []
     bookInstance_ids = []
     num_of_word = BookInstance.objects.filter(status='a',      book__title__contains=request.GET['search_query']).count()
bookInstances = BookInstance.objects.filter(status='a', book__title__contains=request.GET['search_query'])
     for i in bookInstances:
        bookInstance_titles.append(str(i.book))
        bookInstance_ids.append(str(i.id))

    context = {
    . . .
    'num_of_word': num_of_word,
    'bookInstance_titles': bookInstance_titles,
    'bookInstance_ids': bookInstance_ids,
}

我认为问题在于变量（num_of_word和bookInstances）正在尝试访问请求的search_query，但是/ catalog /请求没有搜索查询。经过研究，我仍然不确定如何解决这个问题。

谢谢！

Answer 1

您尝试访问不存在的GET查询。您必须检查request.GET中是否存在search_query或仅对其使用.get函数。见下文：

def index(request):
     . . .
     num_of_word = []
     bookInstance_titles = []
     bookInstance_ids = []
     num_of_word = BookInstance.objects.filter(status='a', book__title__contains=request.GET.get('search_query', '').count()
     bookInstances = BookInstance.objects.filter(status='a', book__title__contains=request.GET.get('search_query', ''))
     for i in bookInstances:
         bookInstance_titles.append(str(i.book))
         bookInstance_ids.append(str(i.id))
    context = {
         . . .
         'num_of_word': num_of_word,
         'bookInstance_titles': bookInstance_titles,
         'bookInstance_ids': bookInstance_ids,
    }

Answer 2

希望它会起作用。根据您的代码使用以下内容。

    if request.method == 'GET' and 'q' in request.GET: #q is search Input field reference 
        num_of_word = []
        bookInstance_titles = []
        bookInstance_ids = []
        num_of_word = BookInstance.objects.filter(status='a', book__title__contains=request.GET.get('search_query', '').count()
        bookInstances = BookInstance.objects.filter(status='a', book__title__contains=request.GET.get('search_query', ''))
        for i in bookInstances:
            bookInstance_titles.append(str(i.book))
            bookInstance_ids.append(str(i.id))
        context = {
            . . .
            'num_of_word': num_of_word,
            'bookInstance_titles': bookInstance_titles,
            'bookInstance_ids': bookInstance_ids,
        }
    else{
        context = {
             . . .
             'num_of_word': "", #What you want to pass
             'bookInstance_titles': "", #What you want to pass
             'bookInstance_ids': "",  #What you want to pass
        }
    }

加载没有搜索查询的URL

2 个答案: