IWMSCacheItemCollection.GetCount (Visual Basic .NET)

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IWMSCacheItemCollection.GetCount (Visual Basic .NET)

The GetCount method retrieves the number of IWMSCacheItemDescriptor objects in the collection.





[out] Reference to an Integer containing the number of cache descriptors.

Return Values

This method does not return a value. To report an error, the plug-in can throw a COMException object to the server. If the plug-in uses the IWMSEventLog object to log error information, it is recommended that it throw NS_E_PLUGIN_ERROR_REPORTED (0xC00D157D). Typically, the server attempts to make plug-in error information available to the server object model, the Windows Event Viewer, and the troubleshooting list in the details pane of the Windows Media Services MMC. However, if the plug-in uses the IWMSEventLog object to send custom error information to the Windows Event Viewer, throwing NS_E_PLUGIN_ERROR_REPORTED stops the server from also logging to the event viewer. For more information about plug-in error information, see Identifying Plug-in Errors.


The IWMSCacheItemDescriptor object retrieves the size, version number, expiration date, and URL of cached content.

Example Code

The following example assumes that the cache plug-in makes use of the .NET DataSet collection of DataTable objects. Each DataRow object in the data table represents one IWMSCacheDescriptor object.

Imports Microsoft.WindowsMediaServices.Interop
Imports System.Runtime.InteropServices

Public Sub GetCount(ByRef Count As Integer) _
  Implements IWMSCacheItemCollection.GetCount

    ' DT is a DataTable object.
    ' Rows is a DataRow object.
      Rows = DT.Select()
      Count = Rows.Length

    Catch Exc As Exception
      Throw New COMException()
    End Try

End Sub


Reference: Add a reference to Microsoft.WindowsMediaServices.

Namespace: Microsoft.WindowsMediaServices.Interop.

Assembly: Microsoft.WindowsMediaServices.dll.

Library: WMSServerTypeLib.dll.

Platform: Windows Server 2003, Enterprise Edition; Windows Server 2003, Datacenter Edition; Windows Server 2008.

See Also

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