Question

我正在接收一个字符串消息并将其分解为块，以便我可以将其发送到短信服务（因此不会为您分解）。在我完成工作以打破这些消息后，我尝试循环生成的数组并执行Web请求。问题是它只适用于第一条消息，然后挂起。片刻之后，我收到一条错误消息，提示“连接意外关闭”。这是在第二次尝试GetResponse（）时发生的;我在这里看到了一些其他帖子，只是说要关闭并处理响应和请求流。这对我来说根本不起作用。这是我目前的代码：

private static void Main(string[] args)
{
    var oldMessage = GetFileString();
    Console.WriteLine(string.Format("Old message: {0}", oldMessage.Length));

    var newMessage = UrlPathEncodeString(oldMessage);
    Console.WriteLine(string.Format("New message: {0}", newMessage.Length));

    var brokenUp = SplitByLength(newMessage, 145).ToArray();
    for(var i = 0; i < brokenUp.Count(); i++)
    {
        brokenUp[i] = brokenUp[i].Insert(0, UrlPathEncodeString(string.Format("({0:D2} of {1:D2})", i + 1, brokenUp.Count())));
        Console.WriteLine(string.Format("Appended length: {0}", brokenUp[i].Length));
    }

    System.Net.ServicePointManager.DefaultConnectionLimit = 100;
    foreach (var block in brokenUp)
    {
        Thread.Sleep(1500);
        SendSms((HttpWebRequest)WebRequest.Create("http://172.20.5.214:90/method/sendsms"), block);
    }
    Console.ReadKey();
}

public static void SendSms(HttpWebRequest request, string message)
{
    //build the request
    var url = "http://ipaddress/method/sendsms";
    //var request = (HttpWebRequest)WebRequest.Create(url);
    request.Method = "POST";
    request.ContentType = "application/x-www-form-urlencoded";

    var fields = "CellNumber={0}&Message={1}";
    fields = string.Format(fields, "16021234567", message);

    var fieldsBytes = Encoding.UTF8.GetBytes(fields);
    request.ContentLength = fieldsBytes.Length;
    var length = fieldsBytes.Length;

    using (var requestStream = request.GetRequestStream())
    {
        requestStream.Write(fieldsBytes, 0, length);

        using (var response = request.GetResponse())
        {
            using (var responseStream = response.GetResponseStream())
            {
                responseStream.Close();
            }
        }
        requestStream.Close();
    }
}

public static byte[] ReadFully(Stream stream)
{
    var buffer = new byte[32768];
    using (var ms = new MemoryStream())
    {
        while (true)
        {
            int read = stream.Read(buffer, 0, buffer.Length);
            if (read <= 0)
                return ms.ToArray();
            ms.Write(buffer, 0, read);
        }
    }
}

Answer 1

如果您无法下载响应的全部内容，我会遇到response.Close似乎挂起的情况。为什么会这样，我不知道，但在致电request.Abort之前拨打Close()来解决问题。不过，我不希望你看到这个问题，除非响应可能有多兆字节。

此外，在调用GetResponse之前未能关闭请求流可能会阻止发送所有数据。我建议在发出请求之前调用requestStream.Close。但同样，您的代码第一次运行而不是后续请求似乎很奇怪。

考虑到我建议的更改，您修改的代码将是：

using (var requestStream = request.GetRequestStream())
{
    requestStream.Write(fieldsBytes, 0, length);
}

using (var response = request.GetResponse())
{
    using (var responseStream = response.GetResponseStream())
    {
        // read the response here.
        request.Abort();
        responseStream.Close();
    }
}

在循环内执行Web请求仅适用于第一遍

1 个答案: