1.修改login_check視圖函數，用戶名密碼正確後，將用戶名寫入cookie
def login_check(request):
username = request.POST.get('username')
password = request.POST.get('password')
remember=request.POST.get('remember')
print(remember)
# print(username + ":" + password)
if username == 'admin' and password == '111':
response = redirect('/index')
if remember=='on':
response.set_cookie('username',username,max_age=7*24*3600)
return response
else:
return redirect('/login')
2.修改login視圖函數，判斷cookie裏面是否有username的key，有的話將username對應的值傳給模板
def login(request):
if 'username' in request.COOKIES:
username = request.COOKIES['username']
else:
username = ''
return render(request, 'booktest/login.html',{'username':username})
3.修改視圖模板
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>登陸頁面</title>
</head>
<body>
<form method="post" action="/login_check">
用戶名:<input type="text" name="username" value="{{username}}"/><br/>
密碼：<input type="password" name="password"/><br/>
<input type="checkbox" name="remember"/>記住用戶名<br/>
<input type="submit" value="登陸">
</form>
</body>
</html>
4.登陸成功後，再次訪問登陸頁面，自動填入用戶名
