IMAQError Event
Syntax
Sub ControlName_IMAQError(StatusCode, ContextID, ContextDescription)
Applies To
Purpose
Fires when an NI-IMAQ error occurs, depending on the value of the ErrorEventMask property. The ErrorEventMask property selects the contexts—configuring, reading data, and so on—for which the CWIMAQ control generates IMAQError events.
Remarks
You can write a global error handler for the CWIMAQ control in the event handler for IMAQError. For example, you can compare the ContextID parameter to the CWIMAQErrorContexts constants in the event handler code to handle errors in certain contexts only.
The value of the ErrorEventMask property determines the contexts for which CWIMAQ generates error events. Typically, you use the IMAQError event only to catch errors while an acquisition is in progress. When configuring, starting, stopping, or resetting an acquisition, you typically test the return value of the CWIMAQ control methods to detect errors. If ExceptionOnError is True, the methods raise an exception on an error condition.
Parameters
StatusCode As Long
The status code for the error.
ContextID As Long
Identifies the context of the error. The CWIMAQErrorContexts constants define the possible values for this parameter.
ContextDescription As String
A textual description of the context.
Example
Private Sub CWIMAQ1_IMAQError(ByVal StatusCode As Long, ByVal ContextID As Long, ByVal ContextDescription As String)
If ContextID = cwimaqAcquiring Then
MsgBox ContextDescription & vbCrLf & CStr(StatusCode)
End If
End Sub