Interface IEventIOCompletion

Description

This interface is exported by I/O Completion event objects.

IEventIOCompletion derives from IEvent.

Methods

GetAttribute

Use of this method is discouraged. All the non-deprecated standard attributes are accessible via properties on the appropriate COM interfaces.

SetAttribute

Use of this method is discouraged. All the non-deprecated standard attributes are accessible via properties on the appropriate COM interfaces.

Close

Closes the resource. Sending the resource's COM object's reference count to zero (and thus destroying the object) also executes a close, but this method may be useful for environments with garbage collection or other facilities that make object lifetimes non-deterministic.

Properties

type

The type of the event. Legal values are:

  • EVENT_IO_COMPLETION
  • EVENT_TRIG
  • EVENT_SERVICE_REQ
  • EVENT_CLEAR
  • EVENT_EXCEPTION
  • EVENT_GPIB_CIC
  • EVENT_GPIB_TALK
  • EVENT_GPIB_LISTEN
  • EVENT_VXI_VME_SYSFAIL
  • EVENT_VXI_VME_SYSRESET
  • EVENT_VXI_SIGP
  • EVENT_VXI_VME_INTR
  • EVENT_TCPIP_CONNECT
  • CUSTOM_EVENT_TYPE

CustomEventTypeNumber

If the type parameter's value is CUSTOM_EVENT_TYPE, this value contains the custom event type.

IOStatus

The HRESULT of the I/O operation.

jobId

The job ID of the I/O operation.

ReturnCount

If successful, the number of bytes written/read in the asynchronous I/O operation.

ReadBuffer

The read/written data in the form of a SAFEARRAY of bytes.

ReadBufferAsString

The read/written data in the form of a BSTR.

See Also

Diagram of VISA COM Interfaces