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CacheDependency.GetUniqueID Method

  • Reference

Definition

Namespace:
System.Web.Caching
Assembly:
System.Web.dll

Retrieves a unique identifier for a CacheDependency object.

public:
 virtual System::String ^ GetUniqueID();
public virtual string GetUniqueID ();
abstract member GetUniqueID : unit -> string
override this.GetUniqueID : unit -> string
Public Overridable Function GetUniqueID () As String

Returns

String

The unique identifier for the CacheDependency object.

Examples

The following code example creates an AggregateCacheDependency object, named aggDep, with two CacheDependency objects in its array. Once aggDep is instantiated, the code calls the GetUniqueID method to generate a unique identifier for both dependencies that aggDep contains and displays the identifiers to the containing page. An item is then added to the Cache, using the Insert method, with aggDep as a dependency.

         ' Create two CacheDependency objects, one to a
         ' text file and the other to an XML file. 
         ' Create a CacheDependency array with these 
         ' two objects as items in the array.
          txtDep = New CacheDependency(Server.MapPath("Storage.txt"))
          xmlDep = New CacheDependency(Server.MapPath("authors.xml"))
          Dim DepArray() As CacheDependency = {txtDep, xmlDep}

          ' Create an AggregateCacheDependency object and 
          ' use the Add method to add the array to it.   
          aggDep = New AggregateCacheDependency()
          aggDep.Add(DepArray)

          ' Call the GetUniqueId method to generate
          ' an ID for each dependency in the array.
          msg1.Text = aggDep.GetUniqueId()
          
          ' Add the new data set to the cache with 
          ' dependencies on both files in the array.
          Cache.Insert("XMLDataSet", Source, aggDep)

Remarks

This method can be particularly useful for tracking multiple instances of the CacheDependency class associated with an item or an application.

The identifier is a combination of either the file name (for a file dependency) or the key name (for a cache-key dependency) and a string that this method assigns to the dependency. In classes that derive from the CacheDependency class, you can override this method to customize how it generates the unique identifier.

Applies to

See also