ASP.NET多站点Session共享

首先，这些站点的Session必须存在sqlserver中。

站点A和站点B的 web.config加入下面代码。

<machineKey validationKey="C50B3C89CB21F4F1422FF158A5B42D0E8DB8CB5CDA1742572A487D9401E3400267682B202B746511891C1BAF47F8D25C07F6C39A104696DB51F17C529AD3CABE"
                    decryptionKey="8A9BE8FD67AF6979E7D20198CFEA50DD3D3799C77AF2B72F" validation="SHA1" />

分别在站点A和站点B中添加一个httpmodule。

　　　　  public class SharedSessionModule : IHttpModule
	{

		#region IHttpModule Members
		/// <summary>
		/// Initializes a module and prepares it to handle requests.
		/// </summary>
		/// <param name="context">An <see cref="T:System.Web.HttpApplication"/>
		/// that provides access to the methods,
		/// properties, and events common to all application objects within an ASP.NET
		/// application</param>
		public void Init(HttpApplication context)
		{
			// Get the app name from config file...
			string appName = ConfigurationManager.AppSettings["ApplicationName"];

			if (!string.IsNullOrEmpty(appName))
			{
				FieldInfo runtimeInfo = typeof(HttpRuntime).GetField("_theRuntime", BindingFlags.Static | BindingFlags.NonPublic);
				HttpRuntime theRuntime = (HttpRuntime)runtimeInfo.GetValue(null);
				FieldInfo appNameInfo = typeof(HttpRuntime).GetField("_appDomainAppId", BindingFlags.Instance | BindingFlags.NonPublic);
				appNameInfo.SetValue(theRuntime, appName);
			}
		}

		/// <summary>
		/// Disposes of the resources (other than memory) used by the module that
		/// implements <see cref="T:System.Web.IHttpModule"/>.
		/// </summary>
		public void Dispose()
		{

		}

		#endregion

	}

两个站点的web.config加入下面代码。

<httpModules>
            <add name="SharedSessionModule" type="AppNameSpace.SharedSessionModule, AppNameSpace, Version=1.0.0.0, Culture=neutral" />
        </httpModules>

如果两个站点的domain name不同，还需要下面一段代码

　　　　　　　　　　　　　　 var session = HttpContext.Current.Session;
			var request = HttpContext.Current.Request;
			var cookie = request.Cookies["ASP.NET_SessionId"];
			if (cookie != null && session != null && session.SessionID != null)
			{
				cookie.Value = session.SessionID;
				cookie.Domain = "yourappdomain.com";
				// the full stop prefix denotes all sub domains  
				cookie.Path = "/"; // default session cookie path root  
			}