(转)利用http 协议的get 和post

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Collections;
using System.IO;
using System.Net;
using System.Text;
using System.Xml;
using System.Xml.Serialization;

namespace MyWebServiceTest
{
	public class RequestHelper
	{
		#region Tip:使用说明
		//webServices 应该支持Get和Post调用，在web.config应该增加以下代码
		//<webServices>
		//  <protocols>
		//    <add name="HttpGet"/>
		//    <add name="HttpPost"/>
		//  </protocols>
		//</webServices>

		//调用示例：
		//Hashtable ht = new Hashtable();  //Hashtable 为webservice所需要的参数集
		//ht.Add("str", "test");
		//ht.Add("b", "true");
		//XmlDocument xx = WebSvcCaller.QuerySoapWebService("http://localhost:81/service.asmx", "HelloWorld", ht);
		//MessageBox.Show(xx.OuterXml);
		#endregion

		/// <summary>
		/// 需要WebService支持Post调用
		/// </summary>
		public static XmlDocument QueryPostWebService(String URL, String MethodName, Hashtable Pars)
		{
			HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(URL + "/" + MethodName);
			request.Method = "POST";
			request.ContentType = "application/x-www-form-urlencoded";
			SetWebRequest(request);
			byte[] data = EncodePars(Pars);
			WriteRequestData(request, data);
			return ReadXmlResponse(request.GetResponse());
		}

		/// <summary>
		/// 需要WebService支持Get调用
		/// </summary>
		public static XmlDocument QueryGetWebService(String URL, String MethodName, Hashtable Pars)
		{
			HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(URL + "/" + MethodName + "?" + ParsToString(Pars));
			request.Method = "GET";
			request.ContentType = "application/x-www-form-urlencoded";
			SetWebRequest(request);
			return ReadXmlResponse(request.GetResponse());
		}

		/// <summary>
		/// 通用WebService调用(Soap),参数Pars为String类型的参数名、参数值
		/// </summary>
		public static XmlDocument QuerySoapWebService(String URL, String MethodName, Hashtable Pars)
		{
			if (_xmlNamespaces.ContainsKey(URL))
			{
				return QuerySoapWebService(URL, MethodName, Pars, _xmlNamespaces[URL].ToString());
			}
			else
			{
				return QuerySoapWebService(URL, MethodName, Pars, GetNamespace(URL));
			}
		}

		private static XmlDocument QuerySoapWebService(String URL, String MethodName, Hashtable Pars, string XmlNs)
		{
			_xmlNamespaces[URL] = XmlNs;//加入缓存，提高效率
			HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(URL);
			request.Method = "POST";
			request.ContentType = "text/xml; charset=utf-8";
			request.Headers.Add("SOAPAction", """ + XmlNs + (XmlNs.EndsWith("/") ? "" : "/") + MethodName + """);
			SetWebRequest(request);
			byte[] data = EncodeParsToSoap(Pars, XmlNs, MethodName);
			WriteRequestData(request, data);
			XmlDocument doc = new XmlDocument(), doc2 = new XmlDocument();
			doc = ReadXmlResponse(request.GetResponse());

			XmlNamespaceManager mgr = new XmlNamespaceManager(doc.NameTable);
			mgr.AddNamespace("soap", "http://schemas.xmlsoap.org/soap/envelope/");
			String RetXml = doc.SelectSingleNode("//soap:Body/*/*", mgr).InnerXml;
			doc2.LoadXml("<root>" + RetXml + "</root>");
			AddDelaration(doc2);
			return doc2;
		}
		private static string GetNamespace(String URL)
		{
			HttpWebRequest request = (HttpWebRequest)WebRequest.Create(URL + "?WSDL");
			SetWebRequest(request);
			WebResponse response = request.GetResponse();
			StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
			XmlDocument doc = new XmlDocument();
			doc.LoadXml(sr.ReadToEnd());
			sr.Close();
			return doc.SelectSingleNode("//@targetNamespace").Value;
		}

		private static byte[] EncodeParsToSoap(Hashtable Pars, String XmlNs, String MethodName)
		{
			XmlDocument doc = new XmlDocument();
			doc.LoadXml("<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:Envelope>");
			AddDelaration(doc);
			//XmlElement soapBody = doc.createElement_x_x("soap", "Body", "http://schemas.xmlsoap.org/soap/envelope/");
			XmlElement soapBody = doc.CreateElement("soap", "Body", "http://schemas.xmlsoap.org/soap/envelope/");
			//XmlElement soapMethod = doc.createElement_x_x(MethodName);
			XmlElement soapMethod = doc.CreateElement(MethodName);
			soapMethod.SetAttribute("xmlns", XmlNs);
			foreach (string k in Pars.Keys)
			{
				//XmlElement soapPar = doc.createElement_x_x(k);
				XmlElement soapPar = doc.CreateElement(k);
				soapPar.InnerXml = ObjectToSoapXml(Pars[k]);
				soapMethod.AppendChild(soapPar);
			}
			soapBody.AppendChild(soapMethod);
			doc.DocumentElement.AppendChild(soapBody);
			return Encoding.UTF8.GetBytes(doc.OuterXml);
		}
		private static string ObjectToSoapXml(object o)
		{
			XmlSerializer mySerializer = new XmlSerializer(o.GetType());
			MemoryStream ms = new MemoryStream();
			mySerializer.Serialize(ms, o);
			XmlDocument doc = new XmlDocument();
			doc.LoadXml(Encoding.UTF8.GetString(ms.ToArray()));
			if (doc.DocumentElement != null)
			{
				return doc.DocumentElement.InnerXml;
			}
			else
			{
				return o.ToString();
			}
		}

		/// <summary>
		/// 设置凭证与超时时间
		/// </summary>
		/// <param name="request"></param>
		private static void SetWebRequest(HttpWebRequest request)
		{
			request.Credentials = CredentialCache.DefaultCredentials;
			request.Timeout = 10000;
		}

		private static void WriteRequestData(HttpWebRequest request, byte[] data)
		{
			request.ContentLength = data.Length;
			Stream writer = request.GetRequestStream();
			writer.Write(data, 0, data.Length);
			writer.Close();
		}

		private static byte[] EncodePars(Hashtable Pars)
		{
			return Encoding.UTF8.GetBytes(ParsToString(Pars));
		}

		private static String ParsToString(Hashtable Pars)
		{
			StringBuilder sb = new StringBuilder();
			foreach (string k in Pars.Keys)
			{
				if (sb.Length > 0)
				{
					sb.Append("&");
				}
				//sb.Append(HttpUtility.UrlEncode(k) + "=" + HttpUtility.UrlEncode(Pars[k].ToString()));
			}
			return sb.ToString();
		}

		private static XmlDocument ReadXmlResponse(WebResponse response)
		{
			StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
			String retXml = sr.ReadToEnd();
			sr.Close();
			XmlDocument doc = new XmlDocument();
			doc.LoadXml(retXml);
			return doc;
		}

		private static void AddDelaration(XmlDocument doc)
		{
			XmlDeclaration decl = doc.CreateXmlDeclaration("1.0", "utf-8", null);
			doc.InsertBefore(decl, doc.DocumentElement);
		}

		private static Hashtable _xmlNamespaces = new Hashtable();//缓存xmlNamespace，避免重复调用GetNamespace
	}
}