Export (0) Print
Expand All

Page.Cache Property

Gets the Cache object associated with the application in which the page resides.

[Visual Basic]
Public ReadOnly Property Cache As Cache
[C#]
public Cache Cache {get;}
[C++]
public: __property Cache* get_Cache();
[JScript]
public function get Cache() : Cache;

Property Value

The Cache object associated with the page's application.

Exceptions

Exception Type Condition
HttpException The Cache is not instantiated.

Remarks

An application's Cache object allows you to store and retrieve arbitrary data on subsequent requests . The cache is not specifically associated with a page or user session. It is used primarily to enhance application performance. For more information, see Caching Application Data.

Example

The following example inserts the sum of two integers into the Cache using the Page.Cache property. It then retrieves the value using the Cache.Get method and writes it to a Label Web server control.

[SampleID='System.Web.Page.Cache_Replacement' SnippetID='1']
--------- Languages displayed= cs, vb ---------
--------- cs ---------
--------- Snippet 1 ---------
    // This is a simple page that demonstrates how to place a value
    // in the Cache from a page, and one way to retrieve the value.
    // Declare two constants, myInt1 and myInt2 and set their values
    // and declare a string variable, myValue.
    const int myInt1 = 35;
    const int myInt2 = 77;
    string myValue;
    
    // When the page is loaded, the sum of the constants
    // is placed in the Cache and assigned a key, key1.
    void Page_Load(Object sender,  EventArgs arg) {
      Cache["key1"] = myInt1 + myInt2;
    
    }
    
    // When a user clicks a button, the sum associated
    // with key1 is retrieved from the Cache using the 
    // Cache.Get method. It is converted to a string
    // and displayed in a Label web control.
    void CacheBtn_Click(object sender, EventArgs e) {
       If Cache["key1"] == null {
          myLabel.Text = "That object is not cached."
       }
       Else { 
          myValue = Cache.Get("key1").ToString();
          myLabel.Text = myValue;
       }
    }
--------- vb ---------
--------- Snippet 1 ---------
   ' This is a simple page that demonstrates how to place a value
   ' in the Cache from a page, and one way to retrieve the value.
   ' Declare two constants, myInt1 and myInt2 and set their values
   ' and declare a string variable, myValue.
   Const myInt1 As Integer = 35
   Const myInt2 As Integer = 77
   Dim myValue As String
   ' When the page is loaded, the sum of the constants
   ' is placed in the Cache and assigned a key, key1.
   Sub Page_Load(sender As [Object], arg As EventArgs)
      Cache("key1")= myInt1 + myInt2
   End Sub 'Page_Load
 
   ' When a user clicks a button, the sum associated
   ' with key1 is retrieved from the Cache using the 
   ' Cache.Get method. It is converted to a string
   ' and displayed in a Label web control.
   Sub CacheBtn_Click(sender As Object, e As EventArgs)
     If Cache("key1") Is Nothing Then
      myLabel.Text = "That object is not cached."
     Else
      myValue = Cache.Get("key1").ToString()
      myLabel.Text = myValue
     End If
      End Sub 'CacheBtn_Click

Requirements

Platforms: Windows 2000, Windows XP Professional, Windows Server 2003 family

See Also

Page Class | Page Members | System.Web.UI Namespace | Cache | Caching Application Data

Show:
© 2014 Microsoft