WebClient 真的对 .NET 3.5 CF 不可用吗？

Question

我的应用面向 Windows CE；它使用紧凑型框架

我复制了一些使用 WebClient 的其他工作代码，但它无法编译，说：“找不到类型或命名空间名称 'WebClient'（您是否缺少 using 指令或程序集参考？）“

我确实有一个“使用 System.Net;”

由于该错误，我还得到，“当前上下文中不存在名称'HttpRequestHeader'”

代码是：

private static void SendXMLFile(string xmlFilepath, string uri)
{
    using (var client = new WebClient())
    {
        client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
        StringBuilder sb = new StringBuilder();
        using (StreamReader sr = new StreamReader(xmlFilepath))
        {
            String line;
            while ((line = sr.ReadLine()) != null)
            {
                sb.AppendLine(line);
            }
        }
        // I don't know why the prepended equals sign is necessary, but it is
        string allLines = "=" + sb.ToString();
        var result = client.UploadString(uri, "POST", allLines);
    }
}

如果 WebClient 可用于我的场景，我需要什么参考/使用？

如果 WebClient 对我的方案不可用，有什么资源/替代方法？

如果没有追索权/替代品，谁可以/将送我一瓶黑莓白兰地？

更新

我正在尝试根据我的情况调整答案，但马上遇到了问题：

HttpWebRequest request = (HttpWebRequest) WebRequest.Create(uri);
request.Method = method;

问题是“方法”未被识别（得到红色波浪的情况和“当前上下文中不存在名称'方法'”

更新 2

我明白了——方法是传入的字符串；我需要的是：

request.Method = "POST";

更新 3

我还不确定这是否真的有效，但它确实可以编译，而且似乎很有意义，所以我会尝试一下：

private static string SendXMLFile(string xmlFilepath, string uri, int timeout)
{
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
    request.KeepAlive = false;
    request.ProtocolVersion = HttpVersion.Version10;
    request.Method = "POST";

    StringBuilder sb = new StringBuilder();
    using (StreamReader sr = new StreamReader(xmlFilepath))
    {
        String line;
        while ((line = sr.ReadLine()) != null)
        {
            sb.AppendLine(line);
        }
        byte[] postBytes = Encoding.UTF8.GetBytes(sb.ToString());
        if (timeout < 0)
        {
            request.ReadWriteTimeout = timeout;
            request.Timeout = timeout;
        }

        request.ContentLength = postBytes.Length;
        request.KeepAlive = false;

        request.ContentType = "application/x-www-form-urlencoded";

        try
        {
            Stream requestStream = request.GetRequestStream();

            requestStream.Write(postBytes, 0, postBytes.Length);
            requestStream.Close();

            using (var response = (HttpWebResponse)request.GetResponse())
            {
                return response.ToString();
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
            request.Abort();
            return string.Empty;
        }
    }
}

Answer 1

WebClient 不存在，尽管拥有它真的不是那么重要。您可以通过 HttpWebRequest 完成您将要执行的大部分操作。

类似的东西（来自 OpenNETCF 扩展）：

private string SendData(string method, string directory, string data, string contentType, int timeout)
{
    lock (m_syncRoot)
    {
        directory = directory.Replace('\\', '/');
        if (!directory.StartsWith("/"))
        {
            directory = "/" + directory;
        }

        string page = string.Format("{0}{1}", DeviceAddress, directory);

        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(page);
#if !WINDOWS_PHONE
        request.KeepAlive = false;
        request.ProtocolVersion = HttpVersion.Version10;
#endif
        request.Method = method;

        // turn our request string into a byte stream
        byte[] postBytes;

        if (data != null)
        {
            postBytes = Encoding.UTF8.GetBytes(data);
        }
        else
        {
            postBytes = new byte[0];
        }

#if !WINDOWS_PHONE
        if (timeout < 0)
        {
            request.ReadWriteTimeout = timeout;
            request.Timeout = timeout;
        }

        request.ContentLength = postBytes.Length;
        request.KeepAlive = false;
#endif
        if (contentType.IsNullOrEmpty())
        {
            request.ContentType = "application/x-www-form-urlencoded";
        }
        else
        {
            request.ContentType = contentType;
        }

        try
        {
            Stream requestStream = request.GetRequestStream();

            // now send it
            requestStream.Write(postBytes, 0, postBytes.Length);
            requestStream.Close();


            using (var response = (HttpWebResponse)request.GetResponse())
            {
                return GetResponseString(response);
            }
        }
        catch (Exception ex)
        {
            Debug.WriteLine(ex.Message);
            request.Abort();
            return string.Empty;
        }
    }
}