INFO: Only Write-Only interfaces Can be Marked as Queued in COM+

ID: Q246625

The information in this article applies to:

Microsoft COM+, version 1.0

SUMMARY

When attempting to configure an interface as Queued in the COM+ Component Services snap-in in Windows 2000, you might find that the option to do so is disabled. This can be because the interface has [out] or "ByRef" parameters, Property Get methods, or has functions that have return values.

MORE INFORMATION

Queued Components allow for method calls to be stored, queued, and executed later when the object is available. Since the information flow is one-way, interfaces which have either Functions , Property Get, or "ByRef" parameters cannot be marked as Queued.

Please note that Visual Basic marks function parameters as "ByRef" by default that is, if neither "ByRef" or "ByVal" is specified. The parameter will be "ByRef"; thus invalidating queuing for the interface.

REFERENCES

For more information on Queued Components see:

MSDN Queued Components topic

Additional query words: Queued Component Services COM+ Queue QC

Keywords : kbCOMPlus kbDSupport kbComPlusQC
Version : :1.0
Platform : WINDOWS
Issue type : kbinfo