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CacheDependency.HasChanged Property

Gets a value indicating whether the CacheDependency object has changed.

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

public bool HasChanged { get; }

Property Value

Type: System.Boolean
true if the CacheDependency object has changed; otherwise, false. The default is false.

You can add an item to an ASP.NET application's Cache with a CacheDependency. When the CacheDependency changes, the item added to the Cache is invalidated and removed from the cache. You can use this property to determine whether a CacheDependency has changed, and recreate the item in the Cache if that has occurred.

The following code example demonstrates using the HasChanged property to determine whether a CacheDependency changed since the previous request for an item in the Cache. The dt value passed in the start parameter is set to DateTime.Now.

// Insert the cache item.
CacheDependency dep = new CacheDependency(fileName, dt);
cache.Insert("key", "value", dep);

// Check whether CacheDependency.HasChanged is true.
if (dep.HasChanged)
  Response.Write("<p>The dependency has changed.");  
else Response.Write("<p>The dependency has not changed.");

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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