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SessionIDManager.CreateSessionID Method

Creates a unique session identifier for the session.

Namespace:  System.Web.SessionState
Assembly:  System.Web (in System.Web.dll)

Public Overridable Function CreateSessionID ( _
	context As HttpContext _
) As String


Type: System.Web.HttpContext
The current HttpContext object that references server objects used to process HTTP requests (for example, the Request and Response properties).

Return Value

Type: System.String
A unique session identifier.



This method is not intended to be called from application code.

The CreateSessionID method returns a unique session identifier that is a randomly generated number encoded into a 24-character string consisting of lowercase characters from a to z and numbers from 0 to 5.

Notes to Inheritors

You can supply a custom session identifier to be used by ASP.NET session state by creating a class that inherits the SessionIDManager class and overriding the CreateSessionID and Validate methods with your own custom implementations. If your custom session ID does not meet the character constraints enforced by the default implementation of the Validate method, you should override the Validate method to provide validation of your custom session identifier. In this case, the SessionIDManager class will ensure that your custom session identifier is URL encoded in the HTTP response and URL decoded from the HTTP request using the Encode and Decode methods, respectively.

The following code example shows a class that inherits the SessionIDManager class and overrides the CreateSessionID and Validate methods with methods that supply and validate a Guid as the SessionID.

Imports System
Imports System.Configuration
Imports System.Web.Configuration
Imports System.Web
Imports System.Web.SessionState

Namespace Samples.AspNet.Session

  Public Class GuidSessionIDManager
    Inherits SessionIDManager

    Public Overrides Function CreateSessionID(context As HttpContext) As String
      Return Guid.NewGuid().ToString()
    End Function

    Public Overrides Function Validate(id As String) As Boolean
        Dim testGuid As Guid = New Guid(id)

        If id = testGuid.ToString() Then _
          Return True

      End Try

      Return False
    End Function

  End Class

End Namespace

To use the custom class demonstrated in this example, configure the sessionIDManagerType attribute of the sessionState Element (ASP.NET Settings Schema) element, as shown in the following example.

  sqlConnectionString="data source=;Integrated Security=SSPI"

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.