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Below is a sample implementation of the class. It is essentially an empty place holder,
except for a private static property currentSession as a shortcut for HttpContext.Current.Session.
It also provides a safety check in case the session is not available within the context. The
class file can be put under an application’s App_Code folder, or Iron Speed Designer’s project
templates’ App_Code folder.
C#: MyAppSession.cs
using System;
using System.Web;
using System.Web.SessionState;
namespace ProjectNamespace.UI {
/// <summary>
/// MyAppSession provides access to session variables as static properties.
/// </summary>
public class MyAppSession {
/// <summary>
/// Private shortcut to HttpContext.Current.Session. Check its availability.
/// </summary>
private static HttpSessionState currentSession {
get {
if (HttpContext.Current.Session == null)
throw new Exception("Session is not available in the current context.");
else
return HttpContext.Current.Session;
}
}
}
}
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Visual Basic .NET: MyAppSession.vb
Imports System
Imports System.Web
Imports System.Web.SessionState
Namespace ProjectNamespace.UI
''' <summary>
''' MyAppSession provides access to session variables as static properties.
''' </summary>
Public Class MyAppSession
''' <summary>
''' Private shortcut to HttpContext.Current.Session. Check its availability.
''' </summary>
Private Shared ReadOnly Property currentSession() As HttpSessionState
Get
If HttpContext.Current.Session = Nothing Then
Throw New Exception("Session is not available in the current context.")
Else
Return HttpContext.Current.Session
End If
End Get
End Property
End Class
End Namespace
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To encapsulate a session variable, add a private static (Shared) string field and a public static (Shared) typed property. The string field serves as the session variable’s key, and the property is the access point of the variable. Below are some sample session variables of different types.
Example I: A bool variable.
C#:
private static string myBoolVarKey = "myBoolVarKey";
public static bool MyBoolVar {
get { return currentSession[myBoolVarKey] != null; }
set {
if (value)
currentSession[myBoolVarKey] = value;
else
currentSession.Remove(myBoolVarKey);
}
}
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Visual Basic .NET:
Private Shared myBoolVarKey As String = "myBoolVarKey"
Public Shared Property MyBoolVar() As Boolean
Get
Return currentSession(myBoolVarKey) <> Nothing
End Get
Set
If value Then
currentSession(myBoolVarKey) = value
Else
currentSession.Remove(myBoolVarKey)
End If
End Set
End Property
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Example II: A value type (int) variable without any default value. Please note that the type is nullable.
C#:
private static string myIntNoDefKey = "key2";
public static int? MyIntNoDefVar {
get { return (int?)currentSession[myIntNoDefKey]; }
set {
if (value != null)
currentSession[myIntNoDefKey] = value;
else
currentSession.Remove(myIntNoDefKey);
}
}
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Visual Basic .NET:
Private Shared myIntNoDefKey As String = "key2"
Public Shared Property MyIntNoDefVar() As System.Nullable(Of Integer)
Get
Return DirectCast(currentSession(myIntNoDefKey), System.Nullable(Of Integer))
End Get
Set
If value <> Nothing Then
currentSession(myIntNoDefKey) = value
Else
currentSession.Remove(myIntNoDefKey)
End If
End Set
End Property
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Example III: A value type (int) variable with a default value.
C#:
private static string myIntKey = "key3";
public static int MyIntVar {
get {
if (currentSession[myIntKey] == null)
return 0;
else
return (int)currentSession[myIntKey];
}
set {
currentSession[myIntKey] = value;
}
}
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Visual Basic .NET:
Private Shared myIntKey As String = "key3"
Public Shared Property MyIntVar() As Integer
Get
If currentSession(myIntKey) = Nothing Then
Return 0
Else
Return DirectCast(currentSession(myIntKey), Integer)
End If
End Get
Set
currentSession(myIntKey) = value
End Set
End Property
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Example IV: A reference type (string) session variable.
C#:
private static string myStrKey = "key4";
public static string MyStrVar {
get { return currentSession[myStrKey] as string; }
set {
if (value != null)
currentSession[myStrKey] = value;
else
currentSession.Remove(myStrKey);
}
}
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Visual Basic .NET:
Private Shared myStrKey As String = "key4"
Public Shared Property MyStrVar() As String
Get
Return TryCast(currentSession(myStrKey), String)
End Get
Set
If value <> Nothing Then
currentSession(myStrKey) = value
Else
currentSession.Remove(myStrKey)
End If
End Set
End Property
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Example V: A read-only, lazy-initialized session variable.
C#:
private static string shoppingCartKey = "shoppingCartKey";
public static ArrayList ShoppingCart {
get {
if (currentSession[shoppingCartKey] == null)
currentSession[shoppingCartKey] = new ArrayList();
return currentSession[shoppingCartKey] as ArrayList;
}
}
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Visual Basic .NET:
Private Shared shoppingCartKey As String = "shoppingCartKey"
Public Shared ReadOnly Property ShoppingCart() As ArrayList
Get
If currentSession(shoppingCartKey) = Nothing Then
currentSession(shoppingCartKey) = New ArrayList()
End If
Return TryCast(currentSession(shoppingCartKey), ArrayList)
End Get
End Property
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