c# - 正确关闭函数返回的 Stream / StreamReader 实例

Question

我现在正在重构一些代码，发现以下函数：

public static StreamReader DoWebRequest(string url, string method)
{
    HttpWebRequest req = WebRequest.Create(url) as HttpWebRequest;
    req.Method = method;
    req.Timeout = System.Threading.Timeout.Infinite;
    HttpWebResponse resp = req.GetResponse() as HttpWebResponse;
    return new StreamReader(resp.GetResponseStream());
}

然后

string result = Helper.DoWebRequest(ServerUrl, "GET").ReadToEnd();

我经常使用流，并且总是将HttpWebResponse resp = req.GetResponse()流式阅读器放入 using 块中。但是在这种特殊情况下我应该怎么做呢？上面的代码是否可以，或者最好将 StreamReader 分配给新变量并在调用 ReadToEnd() 后显式关闭它；（或使用块内部）像这样：

using(StreamReader sr = Helper.DoWebRequest(ServerUrl, "GET"))
{
  string result = sr.ReadToEnd();
}

谢谢

Answer 1

Well, you can always write another function that does both:

public static String ReadToEndAndClose(this StreamReader stream)
{
    using(var sr = stream)
    {
        return sr.ReadToEnd();
    }
}