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Page.Cache Property

  • Reference

Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

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

public:
 property System::Web::Caching::Cache ^ Cache { System::Web::Caching::Cache ^ get(); };
[System.ComponentModel.Browsable(false)]
public System.Web.Caching.Cache Cache { get; }
[<System.ComponentModel.Browsable(false)>]
member this.Cache : System.Web.Caching.Cache
Public ReadOnly Property Cache As Cache

Property Value

Cache

The Cache associated with the page's application.

Attributes
BrowsableAttribute

Exceptions

HttpException

An instance of Cache is not created.

Examples

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

// 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 server 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;
   }
}

  ' 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 server 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

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. For more information on the difference between application caching and page output caching, see ASP.NET Caching Overview.

Applies to

See also