OnWarning Method of the IFRDocumentEvents Interface

This method is implemented on the client-side. It is called by ABBYY FineReader Engine for some of the methods of the FRDocument object. It delivers to the client tips and warnings which occurred during processing. It may also process any Windows messages to avoid an effect that the application "is not responding" during long recognition operations.



HRESULT OnWarning(
  IFRDocument*  Sender,
  int           PageIndex,
  BSTR          Warning,


void OnWarning(
  IFRDocument Sender,
  int        PageIndex,
  string     Warning,
  ref bool   Cancel

Visual Basic .NET

Sub OnWarning( _
  Sender As IFRDocument,  _
  PageIndex As Integer, _
  Warning As String, _
  ByRef Cancel As Boolean _


[in] Refers to the FRDocument object which sends notifications.
[in] This parameter contains the index of the page to which the tip or warning refers. The message can refer not only to one page but to the entire document. In this case, the value of the parameter is -1.
[in] Contains the tip or warning.
[in, out] You may set this variable to TRUE to indicate that the process should be terminated. In this case, the analysis or recognition function that reports the tip returns E_ABORT.

Return values

[C++ only] If this method returns a value other than S_OK, it indicates that an error occurred on the client-side, and in this case the value of the Cancel parameter is not taken into account.


The client implementation of this method must assure that all exceptions thrown inside the method are caught and handled and no exceptions are propagated outside the method. Propagation of an exception outside the method may lead to unpredictable results (such as program termination).

See also



24.03.2023 8:51:52

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