使用HttpWebRequest访问Web服务，并传递Cookie数据

有时候难免会在项目中使用到web服务，可以利用vs生成web服务访问代理。不过呢，我们在这儿使用HttpWebReqeust来访问web服务，并访问Cookie

我们以登录操作为例（Soap 1.1）：

1、提交登录数据，并获取Cookie

System.Net.HttpWebRequest req = System.Net.HttpWebRequest.Create("web服务地址");
req.Method = "POST";
//req.ContentType = "application/x-www-form-urlencoded"
req.ContentType = "text/xml; charset=utf-8";
//此处限定web服务方法
req.Headers.Add("SOAPAction", "\"http://www.demo.com/Login\"");
//这儿必须添加CookieContainer，不然后面得不到Cookie
req.CookieContainer = new System.Net.CookieContainer();
//准备构建Soap内容
StringBuilder soap = new StringBuilder();
// 构建SOAP内容
soap.AppendLine("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
soap.AppendLine("<soap:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">");
soap.AppendLine("  <soap:Body>");
soap.AppendLine("    <Login xmlns=\"http://www.demo.com/\">");
soap.AppendLine("      <username>用户名</username>");
soap.AppendLine("      <password>密码</password>");
soap.AppendLine("    </Login>");
soap.AppendLine("  </soap:Body>");
soap.AppendLine("</soap:Envelope>");
//获取请求的流对象，以方便写入soap内容
System.IO.StreamWriter reqStream = new System.IO.StreamWriter(req.GetRequestStream());
reqStream.Write(soap.ToString());
reqStream.Close();

//获取返回的流对象
System.Net.HttpWebResponse rep = req.GetResponse();
System.IO.StreamReader reader = new System.IO.StreamReader(rep.GetResponseStream());
//输出返回的数据
TextBox1.Text = reader.ReadToEnd();
reader.Close();
rep.Close();
//获取Cookie
System.Net.Cookie cookie = rep.Cookies("cookie名称");
if(cookie != null){
Response.Write(cookie.Value);
}

2、获取登录用户信息（会话访问），将Cookie发送回服务器端

System.Net.HttpWebRequest req = System.Net.HttpWebRequest.Create("http://www.demo.com/webtools/webservice/web/youjuhuiservice.asmx");
req.Method = "POST";
req.ContentType = "text/xml; charset=utf-8";
//请求的web服务方法
req.Headers.Add("SOAPAction", "\"http://www.demo.com/GetOnlineUser\"");
//添加CookieContainer，不然无法传递Cookie数据
req.CookieContainer = new System.Net.CookieContainer();
//创建一个Cookie，此Cookie不是HttpCookie，但结构差不多的
System.Net.Cookie cookie = new System.Net.Cookie("cookie名称", "cookie值");
//设置Cookie作用域
cookie.Domain = www.demo.com;
//将Cookie添加到请求中
req.CookieContainer.Add(cookie);
StringBuilder soap = new StringBuilder();
// 构建SOAP内容
soap.AppendLine("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
soap.AppendLine("<soap:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">");
soap.AppendLine("  <soap:Body>");
soap.AppendLine("    <GetOnlineUser xmlns=\"http://www.demo.com/\" />");
soap.AppendLine("  </soap:Body>");
soap.AppendLine("</soap:Envelope>");

//获取请求的流对象，以方便写入soap内容
System.IO.StreamWriter reqStream = new System.IO.StreamWriter(req.GetRequestStream());
reqStream.Write(soap.ToString());
reqStream.Close();

//获取响应的流对象，以分析获取内容
System.Net.HttpWebResponse rep = req.GetResponse();
System.IO.StreamReader reader = new System.IO.StreamReader(rep.GetResponseStream());
//输出内容
TextBox1.Text = reader.ReadToEnd();
reader.Close();
rep.Close();