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4/8/2010

This function registers with OLE the instance of an EXE application's IMessageFilterinterface, which is to be used for handling concurrency issues. DLL object applications cannot register a message filter.

Syntax 

HRESULT CoRegisterMessageFilter(
  LPMESSAGEFILTER 
lpMessageFilter,
  LPMESSAGEFILTER* 
lplpMessageFilter
);

Parameters

lpMessageFilter

[in] Pointer to the IMessageFilterinterface on the message filter supplied by the application. Can be NULL, indicating that the current IMessageFilterregistration should be revoked.

lplpMessageFilter

[out] Address of IMessageFilter* pointer variable that receives the interface pointer to the previously registered message filter.

If there was no previously registered message filter, the value of * lplpMessageFilteris NULL.

The value contained in the output variable is rarely NULL, however, containing instead a pointer to the default message filter.

Return Value

S_OK

The IMessageFilterinstance registered or revoked successfully.

S_FALSE

Error registering or revoking IMessageFilterinstance.

Remarks

To determine whether the platform supports this function, see Determining Supported COM APIs.

Requirements

Header objbase.h
Library ole32.lib
Windows Embedded CE Windows CE 3.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also

Reference

COM Functions