How To Use the WebBrowser Control to Open an Office Document (243058)

MORE INFORMATION

ActiveX Documents are embeddable OLE objects that behave more like ActiveX controls than traditional OLE objects. Unlike a normal embedded object, an ActiveX Document is not designed to be a contained object in a larger document. Instead, it is considered a complete document in itself, which is merely being viewed by a viewer (such as Internet Explorer) or is being collected into a single resource with other documents (such as a Binder file).

While Microsoft Visual Basic does not currently support hosting ActiveX Documents directly, you can work around this limitation by using the capabilities of Internet Explorer and its WebBrowser control. The WebBrowser control (Shdocvw.dll) is a part of Internet Explorer and can only be used on systems that have Internet Explorer installed.

Creating a Visual Basic Application that Opens Office Documents

Use the following steps to create a Visual Basic application that opens Office documents:

1. Start Visual Basic and create a new Standard project. Form1 is created by default.
2. From the Project menu, select Components to open the Components dialog box. In the Components dialog box, add references to the Microsoft Common Dialog Control and the Microsoft Internet Controls. Click OK to add the items to the toolbox.
3. Add an instance of the WebBrowser control, CommonDialog control, and a CommandButton to Form1.
4. Next, add the following code into the Code window for Form1:

   Option Explicit
   
   Dim oDocument As Object
   
   Private Sub Command1_Click()
      Dim sFileName As String
      
    ' Find an Office file...
      With CommonDialog1
         .FileName = ""
         .ShowOpen
         sFileName = .FileName
      End With
      
    ' If the user didn't cancel, open the file...
      If Len(sFileName) Then
         Set oDocument = Nothing
         WebBrowser1.Navigate sFileName
      End If
   End Sub
   
   Private Sub Form_Load()
      Command1.Caption = "Browse"
      With CommonDialog1
         .Filter = "Office Documents " & _
         "(*.doc, *.xls, *.ppt)|*.doc;*.xls;*.ppt"
         .FilterIndex = 1
         .Flags = cdlOFNFileMustExist Or cdlOFNHideReadOnly
      End With
   End Sub
   
   Private Sub Form_Unload(Cancel As Integer)
      Set oDocument = Nothing
   End Sub
   
   Private Sub WebBrowser1_NavigateComplete2(ByVal pDisp As Object, _
   URL As Variant)
      On Error Resume Next
      Set oDocument = pDisp.Document
   
      MsgBox "File opened by: " & oDocument.Application.Name
   End Sub
   					

5. Press F5 to run the project. When you select the Browse button, the Open dialog box appears allowing you to navigate to a Word, Excel or PowerPoint file. Choose Open and the document should open inside the WebBrowser control. A message box then appears that displays the name of the Office application that opened the file.

Considerations When Using the WebBrowser Control

The following should be considered when you use the WebBrowser control:

• The WebBrowser control navigates to documents asynchronously. This means that when you call WebBrowser1.Navigate, the call returns control to your Visual Basic application before the document has been completely loaded. If you plan on Automating the contained document, you need to use the NavigateComplete2 event to know when the document has finished loading. Use the Document property of the WebBrowser object passed in to get a reference to the Office document object, which, in the preceding code, is set to oDocument.
• The WebBrowser control does not support menu merging. If you need the document's menu items to appear with your Visual Basic menu, you must use the OLE container control instead.
• The WebBrowser control generally hides any docked toolbars before displaying an Office document. You can use Automation to show a floating toolbar using code such as this:

     With oDocument.Application.CommandBars("Standard")
        .Position = 4 '[msoBarFloating]
        .Visible = True
     End With
  					

  Newer versions of Internet Explorer (5.0 and greater) also allow you to display docked toolbars using the following code:

   ' This is a toggle option, so call it once to show the 
   ' toolbars and once to hide them. This works with Internet Explorer 5
   ' but often fails to work properly with earlier versions...
     WebBrowser1.ExecWB OLECMDID_HIDETOOLBARS, OLECMDEXECOPT_DONTPROMPTUSER
  					

• There are several known issues with having more than one WebBrowser control in a project, and having each control loaded with the same type of Office document (that is, all Word documents, or all Excel spreadsheets). It is recommended that you only use one control per project, and navigate to one document at a time.
  
  The most common problem is with Office Command Bars, which appear disabled. If you have two WebBrowser controls on the same form, both loaded with Word documents, and you have displayed toolbars using one of the preceding techniques, only one set of toolbars will be active and work correctly. The other will be disabled and cannot be used.
• To clear the WebBrowser of its current contents, in the Click event of another command button (or in some other appropriate place in your code), navigate to the default blank page using this code:

     WebBrowser1.Navigate "about:blank"