在视图中获取会话变量-Django

Question

如果用户刚刚填写了上一页上的表单，我正在尝试将get请求值分配给symbol。我可以导航到其他页面并请求会话变量，但是当我返回索引时，它不再存在。

def index(request):

    if 'symbol' in request.GET:
        symbol = request.GET.get('symbol', '')
        request.session['symbol'] = symbol
    elif not request.session.get('symbol', 'none'):
        symbol = request.session['symbol']

    return render(request, 'backtests/earnings.html', {'symbol' : symbol})

我知道此代码有一些错误，但我真的不知道该在哪里去。截至目前，我正在收到错误

分配前引用的本地变量'符号

Answer 1

尝试这个

def index(request):
if request.method == "GET":
    symbol = request.GET.get('symbol', None)
    if symbol is not None or symbol != "":
        request.session['symbol'] = symbol
    else:
        symbol = request.session['symbol']
    return render(request, 'backtests/earnings.html', {'symbol': symbol})
else:
    redirect to path

Answer 2

我弄清楚了...

def index(request):
    if 'symbol' in request.GET:
        symbol = request.GET.get('symbol',' None')
        request.session['symbol'] = symbol
    else:
        symbol = request.session['symbol']