c# - RestSharp 在服务器上抛出 NullReferenceException

Question

我有一段简单的代码:

try
{
    this.client.ExecuteAsync<Answer>(request, response =>
        {
            if (response.ResponseStatus == ResponseStatus.Completed)
                callback(response.Data);
            ...
        });
}
catch (WebException ex) {...}

并且它在 if 行中抛出 NullReferenceException，因为响应为空。 我该怎么做才能收到有关服务器关闭的消息？

Answer 1

只需为您的响应添加一个空检查:

try
{
    this.client.ExecuteAsync<Answer>(request, response =>
        {
            if (response != null && response.ResponseStatus == ResponseStatus.Completed)
                callback(response.Data);
            else
            {
               // add logic here to handle bad case
            }
        });
}
catch (WebException ex) {...}