Base directory of file to be viewed

The BaseDir property must be set to the directory of the document to be viewed. The document may contain multiple images that are stored in subdirectories. In order for the control to load these images, the BaseDir property must specify the base directory containing the document. If the BaseDir property is not set then these images will not appear in the document.

The BaseDir property must be specified before invoking the Display method.

This property can be changed at design time, or at run time. There is no default value for this property.

WebViewer.FileName = "c:\temp\index.htm"

WebViewer.BaseDir = "c:\temp"

File to be viewed.

The FileName property must be specified before invoking the Display method. This property must be set to the path and name of the document to viewed.

The WebViewer ActiveX control supports the following file formats:

This property can be changed at design time, or at run time. There is no default value for this property.

WebViewer.FileName = "c:\temp\index.htm"

Local error has occurred.

The OnError event occurs when a property is accessed in an illegal way or when a connection with the remote server cannot be established. The table below lists all possible error codes delivered by this event.

The following describes each error in more detail.

ERR_IN_ACTION
Another action is already in progress.

ERR_CANNOT_PERFORM_ACTION
Unable to initialize the underlying Distinct support files. There may be a license violation.

ERR_FILE_NOT_DEFINED
File not specified. The FileName property must be set before the Display method is invoked.

ERR_UNABLE_TO_DISPLAY
Unable to display file. The control was unable to display the file. The document type may not be supported by the control.

Sub WebViewer_OnError (ErrorCode As Integer)
If ErrorCode = ERR_UNABLE_TO_DISPLAY Then
MsgBox "Unable to display file", 64, "Sample Program"
End If
End Sub

Url link information.

This event occurs whenever a link is clicked within an HTML document.

The URL for the link is passed as the argument. This information can be used to obtain the link documents.

The application can use this Url information, in conjunction with the HTTP ActiveX control, to download the document for the link, and then view it using the WebViewer ActiveX control.

Sub WebViewer_OnLink (Url As String)
' display url
Message = "You have clicked on " + Url
MsgBox Message, 64, "Sample Program"
End Sub

Report progress during display.

The OnReportProgress event occurs several times during the Display method to inform the application of the progress. It delivers the number of bytes of the file currently displayed.

The parameters Number and Total represent the number of bytes currently displayed and the total length of the file.

As the display proceeds, one or more OnReportProgress events will occur to deliver the number of bytes displayed so far. The application can process this data and display the progress (eg. update a progress bar or status bar).

Sub WebViewer_OnReportProgress (Bytes As Long, Total As Long)
' display number of bytes displayed
NumBytes = NumBytes + Bytes
StatusBar.Panels(2).Text = "Bytes: " & NumBytes & " / " & Total
End Sub

Report status during display.

The OnReportStatus event occurs several times during the Display method to inform the application of the status of the request.

The Status parameter gives a textual information about the status of the display. For example, the Status parameter may be "Reading File" or "Finished".

As the display proceeds, one or more OnReportStatus events will occur to keep the application informed. The application can process this data and display the status (eg. update a status bar).

Sub WebViewer_OnReportStatus (Status As String)
' display transaction status
StatusBar.Panels(1).Text = "Status: " + Status
End Sub

Display document.

To display the contents of a file, invoke the Display method. The FileName property must be set before calling this method. The OnReportProgress and OnReportStatus events will occur during this method.

If an error occurs, then the OnError event will be fired. The application should set a flag in the OnError event, so that it can determine if the function was successful. In addition, the application may want to display an error message in the OnError event to inform the user of the error. Please check the reference page of the OnError event for a complete listing of error codes.

The Display method returns True if successful; otherwise, it returns False.

Result = WebViewer.Display ()

Initialize various components.

The Start method initializes various components of the WebViewer control. This method must be called before calling the Display method. The Display method will fail if the control is not initialized.

Usually the Start method is called when the application is loaded. The Stop method must be called before the application quits to cleanup any initialized components.

The Start method returns True if successful, otherwise, it returns False.

Result = WebViewer.Start ()

Cleanup initialized components.

The Stop method cleans up the various components initialized at the Start method. This method must be called before quitting the application. Usually the Start method is called when the application is loaded and the Stop method is called just before the application quits.

To ensure proper behavior of the WebViewer control, the application must initialize and cleanup in the manner described.

The Stop method returns True if successful, otherwise, it returns False.

Result = WebViewer.Stop ()