c# - 为什么我在执行 HTTP POST 时用完了流的字节数？

Question

这让我抓狂:

    WebRequest request = WebRequest.Create(url);
    request.Method = "POST";
    request.ContentType = "application/x-www-form-urlencoded";
    request.ContentLength = Encoding.UTF8.GetByteCount(data);
    Stream reqs = request.GetRequestStream();
    StreamWriter stOut = new StreamWriter(reqs, Encoding.UTF8);
    stOut.Write(data);
    stOut.Flush();

我得到一个异常，我用完了流中的字节......但我使用了相同的编码来获取字节数!

使用 ASCII 这不会失败。这是因为Windows喜欢添加的UTF-8 BOM吗？

Answer 1

这可能是 BOM；尝试使用不带 BOM 的显式编码:

Encoding enc = new UTF8Encoding(false);
...
request.ContentLength = enc.GetByteCount(data);
...
StreamWriter stOut = new StreamWriter(reqs, enc);

更简单；切换到 WebClient 而不是尝试自己处理它；用这个发布表单非常容易:

    using (var client = new WebClient())
    {
        var data = new NameValueCollection();
        data["foo"] = "123";
        data["bar"] = "456";
        byte[] resp = client.UploadValues(address, data);
    }

或者使用代码 from here :

  byte[] resp = client.Post(address, new {foo = 123, bar = 546});