可能对标有 notnull 属性的实体赋值

Question

我在request.GetResponse().GetResponseStream() 收到此警告我应该如何处理？

public void GetUserList(string url)
{
    var request = (HttpWebRequest) WebRequest.Create(url);
    string response;

    using (var stream = new StreamReader(request.GetResponse().GetResponseStream()))
    {
        response = stream.ReadToEnd();
    }

    response = DelimiterStrings.Aggregate(response, (current, delim) => current.Replace(delim, "\n"));

    foreach (var line in response.Split(DelimiterChars))
    {
        MainWindow.UserList.Add(line);
    }
}

Resharper 不知道如何“修复它”

Answer 1

如评论所述，首先分配响应流并检查它是否为空，如下所示：

public void GetUserList(string url)
{
  var request = (HttpWebRequest)WebRequest.Create(url);
  var responseStream = request.GetResponse().GetResponseStream();
  if (responseStream != null)
  {
    string response;
    using (var stream = new StreamReader(responseStream))
    {
      response = stream.ReadToEnd();
    }
    response = DelimiterStrings.Aggregate(response, (current, delim) => current.Replace(delim, "\n"));
    foreach (var line in response.Split(DelimiterChars))
    {
      MainWindow.UserList.Add(line);
    }
  }
}

Answer 2

把它分开：

var sourceStream = request.GetResponse().GetResponseStream();
Contract.Assume(sourceStream != null); // Let Resharper know it can't be null.

using (var stream = new StreamReader(sourceStream))

这具有记录和检查您的假设的优势！