The remote server returned an error: (417) Expectation failed

今天利用twitter的search api做个搜索，做了个小demo。新建了个项目，直接在test页面的Page_Load里面写下了如下测试代码。

　　　　 protected void Page_Load(object sender, EventArgs e)

{
string urlPost = "http://search.twitter.com/search.json";

string postData = "q=twitterapi";

UTF8Encoding encoding = new UTF8Encoding();
byte[] byteData = encoding.GetBytes(postData);


HttpWebRequest request = (HttpWebRequest)WebRequest.Create(urlPost);

request.Method = "POST";

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

request.ContentLength = byteData.Length;


Stream requestStream = request.GetRequestStream();

requestStream.Write(byteData, 0, byteData.Length);

requestStream.Close();


HttpWebResponse response = (HttpWebResponse)request.GetResponse();


Stream receiveStream = response.GetResponseStream();


StreamReader readStream = new StreamReader(receiveStream, Encoding.UTF8);


Response.Write("Response stream received.");

Response.Write(readStream.ReadToEnd());

response.Close();

readStream.Close();

}

可惜出现了“The remote server returned an error: (417) Expectation failed”的错误。

开始以为是“长城防火墙”的关系，可是连上vpn后还是一样，于是去网上找解决办法，终于然我找到了原因所在。

“该错误可能是客户端网络环境引起的(don't support "100 continue" expectation)，在程序的配置文件中加上下面部分试试。” 原文地址：http://0e2.net/post/1184.html

<configuration>
<system.net>
<settings>
<servicePointManager expect100Continue="false" />
</settings>
</system.net>
</configuration>

测试，成功！！