这几天一直在学习WebService的知识。正好现在有一个项目，需要在WebService实现如下接口：
String Login(string username, string password) // 登录方法，返回值用来指名是不是登录成功，并且这个值在之后的接口中用来找到相对应的服务器上的session。
因此WebService需要使用到Session，而网上大部分资料是说WebService是无状态的（StateLess），不怎么支持Session。因此难题出现了，首先在Web Serivice
放上声明如下Attribute，[WebMethod(EnableSession = true)]，此为表示在webService上能使用Session。
现在放上我写的WebService的例子代码(service端)：
/// <summary>
/// Summary description for Service1
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.ComponentModel.ToolboxItem(false)]
// To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
[System.Web.Script.Services.ScriptService]
public class Bussiness : System.Web.Services.WebService
{
[WebMethod(Description = "登录方法，返回值用来指名是不是登录成功，并且这个值在之后的接口中用来找到相对应的服务器上的session",
EnableSession = true)]
public string Login(string username, string password)
{
string state = "";
if (IsLogin(username))
state = "Logined";
else
{
state = UserHelper.Login(username, password);
if (state != null && state != "Failed")//
{
//Session.Timeout = 1;
Session[state] = username;
}
}
return state;
}
[WebMethod(Description = "判断是否登录",
EnableSession = true)]
private bool IsLogin(string name)
{
if (name != null && Session[name]!=null&& Session[name].ToString() == name)
return true;
return false;
}
客户端代码，我用的是soap方式写的，soap方式調用WebService的方法，我参看了《Programing Web Service with SOAP》。具体方式参看第三章的。我的客户端SOAP代码（我新建一个类）如下：
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Diagnostics; using System.Web.Services; using System.Web.Services.Protocols; using System.Xml.Serialization; namespace Test { [WebServiceBinding(Name = "BusServiceSoap", Namespace = "http://tempuri.org/")] public class BusService : SoapHttpClientProtocol { public BusService() { // this.Url = "http://localhost:4243/Bussiness.asmx"; this.Url = "http://localhost/Bussiness/Bussiness.asmx"; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/Login", RequestNamespace = "http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped)] public string Login(string username, string password) { object[] result = this.Invoke("Login", new object[] { username, password }); return (string)result[0]; } } }客户点調用代码，也就是用户端的調用代码，我写的是控制台的测试代码，如下：
namespace Test { public class Program { static void Main(string[] args) { string name = "admin"; string password = "123"; TestLogin tl = new TestLogin(name, password); string state = tl.Login(); Console.WriteLine("State = " + state); state = tl.Login(); Console.WriteLine("State = " + state); Console.Read(); } } public class TestLogin { public string name = ""; public string psw = ""; BusService bus = new BusService(); public TestLogin(string name, string psw) { this.name = name; this.psw = psw; } public string Login() { return bus.Login(this.name, this.psw); } } }写到这里进行运行，感觉一切应该按照自己想想的正确的打印出来。打印结果应该是如下这样的：
State = admin
State = Logined
结果实际运行的效果与自己设想的不太一样，实际运行的结果是
State = admin
State = admin
这样的运行结果说明，WebService 的Server端的Session，根本没有保存。通过断点调试发现，第二次读取的Session为空，就是没有保存。
因此只在Server端进行声明EnableSession = true，是不够的，这只是说明Server端现在能用session了。
经过上网查阅资料得知：要想使用Session，在进行上一步的声明之后，还要在客户端实例话WebService对象时，对其CookieContainer也要进行初始化方可使用Session的存储状态。另外在多个webservice代理中，只要含有相同的cookie,就能共用相同的session，其中的cookie通过代理类的CookieContainer.GetCookies(new Uri(s.Url))["ASP.NET_SessionId"]取得，如果其他的webserivce代理类需要用相同的session则可以用CookieContainer.Add方法，将取得的cookie加入即可（还没进行测试）。
知道了如何使用后，修改客户端的Soap代码即可，修改后的代码如下：
[WebServiceBinding(Name = "BusServiceSoap", Namespace = "http://tempuri.org/")] public class BusService : SoapHttpClientProtocol { private static System.Net.CookieContainer cookieContainer; static BusService() { cookieContainer = new System.Net.CookieContainer(); } public BusService() { this.Url = "http://localhost:4243/Bussiness.asmx"; this.CookieContainer = new System.Net.CookieContainer(); /// this.Url = "http://localhost/Bussiness/Bussiness.asmx"; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/Login", RequestNamespace = "http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped)] public string Login(string username, string password) { object[] result = this.Invoke("Login", new object[] { username, password }); return (string)result[0]; } }修改完了之后，进行测试，测试结果与设想的结果一样。
本文的一些内容出自http://63542424.blog.163.com/blog/static/18883900201161632532355/
PS：新手学习WebService的拙见，还望高手给出意见，或者推荐一些webService相关的经典书籍，小生在此不胜感激。
上面的soap端写的代码似乎还是有写问题，原因就是cookieContainer对象可能不一致，会导致服务端Session丢失。改进策略是基于单例模式的设计模式的方法进行修改的，修改的代码如下，这样就可以保证在程序中使用相同的CookieContainer进而保证Session不会意外丢失。
namespace Test { [WebServiceBinding(Name = "BusServiceSoap", Namespace = "http://tempuri.org/")] public class BusService : SoapHttpClientProtocol { private static System.Net.CookieContainer cookieContainer; private static BusService instance; static BusService() { cookieContainer = new System.Net.CookieContainer(); instance = new BusService(); instance.CookieContainer = cookieContainer; } private BusService() { this.Url = "http://localhost:4243/Bussiness.asmx"; //this.CookieContainer = new System.Net.CookieContainer(); //this.Url = "http://localhost/Bussiness/Bussiness.asmx"; } public static BusService getInstance() { if (instance == null) instance = new BusService(); return instance; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/Login", RequestNamespace = "http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped)] public string Login(string username, string password) { object[] result = this.Invoke("Login", new object[] { username, password }); return (string)result[0]; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/AnalyzePrescription", RequestNamespace ="http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped )] public int AnalyzePrescription(string name, List<Student> message) { object[] results = this.Invoke("AnalyzePrescription",new object[]{name,message}); return (int)results[0]; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/IsFinishedAnalysis", RequestNamespace = "http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped )] public bool IsFinishedAnalysis(string name, int postion) { object[] results = this.Invoke("IsFinishedAnalysis", new object[] { name, postion }); return (bool)results[0]; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/GetAnalyzedResult", RequestNamespace = "http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped )] public Result GetAnalyzedResult(string name, int postion) { object[] results = this.Invoke("GetAnalyzedResult", new object[] { name, postion }); return (Result)results[0]; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/Release", RequestNamespace = "http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped )] public bool Release(string name, int postion) { object[] results = this.Invoke("Release", new object[] { name, postion }); return (bool)results[0]; } [System.Web.Services.Protocols.SoapDocumentMethod( "http://tempuri.org/LoginOut", RequestNamespace = "http://tempuri.org/", ResponseNamespace = "http://tempuri.org/", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped )] public bool LoginOut(string name) { object[] results = this.Invoke("Release", new object[] { name }); return (bool)results[0]; } } }PS ：单例模式（Singleton）学习的文章： http://blog.csdn.net/wziyx513225244/article/details/6649652