如果发生JWT异常，如何重定向

How to redirect my laravel webpage to login route if I got a message A token is required from JWTException.

You could check the token using a middleware:

class CheckTokenMiddleware
{
    public function handle($request, Closure $next)
    {
        // Check token here.
        if (!checkToken($request->token)) {
            return redirect('login');
        }

        return $next($request);
    }
}