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# OnLocked Method of the IDocumentViewerEvents Interface

> OnLocked method of the IDocumentViewerEvents Interface in ABBYY FineReader Engine Visual Components on Windows — This method is implemented on the client-side.

This method is implemented on the client-side. It is called after [Document Viewer](/fine-reader/engine/visual-components-reference/documentviewer) has been locked or unlocked. Document Viewer can be locked automatically before the beginning of a long-term processing operation and unlocked after the end of it. The component also can be locked or unlocked via the [IDocumentViewer::Locked](/fine-reader/engine/visual-components-reference/documentviewer#locked) property.

The method delivers to the client information on whether the component is locked or unlocked.

## Syntax

### C++

```cpp theme={null}
HRESULT OnLocked( VARIANT_BOOL Value );
```

### C\#

```csharp theme={null}
void OnLocked( bool Value );
```

### Visual Basic .NET

```vb theme={null}
Sub OnLocked(Value As Boolean)
```

## Parameters

Value

\[in] Specifies whether the component is locked or unlocked. If the parameter is TRUE, the component has been locked. If the parameter is FALSE, the component has been unlocked.

## Return values

\[C++ only] If this method returns a value other than S\_OK, it indicates that an error occurred on the client-side.

## Remarks

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

[IDocumentViewerEvents](/fine-reader/engine/visual-components-reference/idocumentviewerevents)