CacheDependency.HasChanged Property
Definition
Important
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Gets a value indicating whether the CacheDependency object has changed.
public:
property bool HasChanged { bool get(); };
public bool HasChanged { get; }
member this.HasChanged : bool
Public ReadOnly Property HasChanged As Boolean
Property Value
true
if the CacheDependency object has changed; otherwise, false
. The default is false
.
Examples
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.");
' Insert the cache item.
Dim dep As New CacheDependency(fileName, dt)
myCache.Insert("key", "value", dep)
' Check whether CacheDependency.HasChanged is true.
If dep.HasChanged Then
Response.Write("<p>The dependency has changed.")
Else
Response.Write("<p>The dependency has not changed.")
End If
Remarks
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.
Applies to
See also
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