Newsgroup: it.comp.lang.visual-basic
Titolo: DDE

Quale è l'indirizzo da inserire in .linktopic e in .linkitem per fare comunicare 2 
applicazioni in VB5 ad esempio collegare la label1 dell'eseguibile prova.exe in 
c:\documenti(destinazione) alla label1 del programma prova2.exe(origine))?
L'help è inesauriente!
Vi Ringrazio.


Questo l'ho trovato nel CD MSDN
Knowledge Base
Example of Client-Server DDE Between Visual Basic Applications
Article ID: Q74861 
Creation Date: 31-JUL-1991
Revision Date: 21-JUN-1995 
The information in this article applies to: 
- Standard and Professional Editions of Microsoft Visual Basic for 
  Windows, versions 2.0 and 3.0
- Microsoft Visual Basic programming system for Windows, version 1.0 
SUMMARY 
This article outlines the steps necessary to initiate dynamic data exchange
(DDE) between a Microsoft Visual Basic destination application and a Visual
Basic source application. 
This article demonstrates how to: 
•Create a Visual Basic application to function as a DDE source. •Create a
Visual Basic application to function as a DDE destination. •Initiate a
manual DDE link (information updated upon request from the destination)
between the destination application and the source application. •Use
LinkRequest to update information in the destination application from
information in the source application. •Initiate a automatic DDE link
(information updated automatically from source to destination) between the
destination application and the source application. •Use LinkPoke to send
information from the destination application to the source application.
•Change the LinkMode property between automatic and manual. 
MORE INFORMATION 
This information is included with the Help file provided with Microsoft
Professional Toolkit for Visual Basic version 1.0, Microsoft Visual Basic
version 2.0, and Microsoft Visual Basic version 3.0. 
A destination application sends commands through DDE to the source
application to establish a link. Through DDE, the source provides data to
the destination at the request of the destination or accepts information at
the request of the destination. 
Step-by-Step Example 
The steps below show how to establish a DDE conversation between two Visual
Basic applications. 
STEP ONE: Create the Source Application in Visual Basic 
1.Start a new project in Visual Basic. Form1 is created by default.
2.Change the Caption property of Form1 to Source. 3.Change the Form1
LinkMode property to 1 - Source. 4.Put a Text Box (Text1) on Form1. 5.Save
the form and project with the name SOURCE. 6.From the File menu, choose
Make EXE File. In the Make EXE File dialog box, choose OK to accept
SOURCE.EXE as the name of the EXE file. 
STEP TWO: Create the Destination Application in Visual Basic 
1.From the File menu, choose New Project. Form1 is created by default.
2.Change the Caption property of Form1 to Destination. 3.Add the following
controls to Form1, and give them the properties indicated: 
Default Name Caption Name ----------------------------------------- Text1
(Not applicable) Text1 Option1 Manual Link ManualLink Option2 Automatic
Link AutomaticLink Command1 Poke Poke Command2 Request Request 4.Add the
following code to the General Declaration section of Form1: 
Const AUTOMATIC= 1 Const MANUAL = 2 Const NONE = 0 
'(NOTE: For Visual Basic version 1.0, also add the following ' constants:
'Const True = -1 'Const False = 0 5.Add the following code to the Load
event procedure of Form1: 
Sub Form_Load () 
      'This procedure will start the VB source application.
      z% = Shell("SOURCE", 1)
      z% = DoEvents()   'Causes Windows to finish processing Shell command.
      Text1.LinkMode = NONE   'Clears DDE link if it already exists.
      Text1.LinkTopic = "Source|Form1"   'Sets up link with VB source.
      Text1.LinkItem = "Text1"           'Set link to text box on source.
      Text1.LinkMode = MANUAL            'Establish a manual DDE link.
      ManualLink.Value = TRUE            'Sets appropriate option button.
End Sub 6.Add the following code to the Click event procedure of
ManualLink: 
Sub ManualLink_Click () 
      Request.Visible = TRUE    'Make request button valid.
      Text1.LinkMode = NONE     'Clear DDE Link.
      Text1.LinkMode = MANUAL   'Reestablish new LinkMode.
End Sub 7.Add the following code to the Clink event procedure of
AutomaticLink: 
Sub AutomaticLink_Click () 
      Request.Visible = FALSE   'No need for button with automatic link.
      Text1.LinkMode = NONE     'Clear DDE Link.
      Text1.LinkMode = AUTOMATIC   'Reestablish new LinkMode.
End Sub 8.Add the following code to the Click event procedure of Request: 
Sub Request_Click () 
      'With a manual DDE link, this button will be visible, and when
      'selected it will request an update of information from the source
      'application to the destination application.
      Text1.LinkRequest
End Sub 9.Add the following code to the Click event procedure of Poke: 
Sub Poke_Click () 
      'With any DDE link, this button will be visible, and when it's
      'selected, will poke information from the destination application
      'into the source application.
      Text1.LinkPoke
End Sub 
STEP THREE: Run the Visual Basic Destination Application 
Choose one of these options: 
•Run the Visual Basic destination application from the VB.EXE environment
by skipping to step 4 below. •Save the application. Then create an .EXE
file and run it from Windows by beginning with step 1 below. 
1.From the File menu, choose Save, and save the form and project with the
name DEST. 2.From the File menu, choose Make EXE File, and give it the name
DEST.EXE. 3.Exit the Visual Basic environment (VB.EXE). 4.Run the
application from Windows if it's an .EXE file or from the VB.EXE
environment. 5.Form1 of the destination application will load and the
source application will automatically start. 
STEP FOUR: Experiment with DDE Between Visual Basic Applications 
1.Try typing some text into the source application's text box. Then click
the Request button. The text appears in the destination application's text
box. 2.Click the Automatic Link button and then type some more text into
the source application's text box. The text is automatically updated in the
destination application's text box. 3.Type some text into the destination
application's text box. Then click the Poke button to send the text to the
source application's text box. 
For additional information on dynamic data exchange (DDE) between Visual
Basic and other Windows-based applications, query on the following words in
the Microsoft Knowledge Base: 
   DDE and Visual Basic
------------------------------------------------------------------------
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Additional reference words: 1.00 2.00 3.00
KBCategory: kbinterop kbprg kbcode
KBSubcategory: IAPDDE