public async Task InvokeHttpContext httpContext var policy = PolicyHandleExceptionWaitAndRetryAsync_limit i = _duration; await policyExecuteAsyncasync =

public async Task Invoke(HttpContext httpContext) { var policy = Policy.Handle() .WaitAndRetryAsync(_limit, i => _duration);

await policy.ExecuteAsync(async () =>
{
    if (_limit >= 0)
    {
        throw new Exception("请求太快");
    }
});

await _next(httpContext);

}