WithEvents

[danasegarane]

Dear All,
What is the use of with Events in VB

Dana

[iPrank]

It means that, the Object you are declaring with the WithEvents statement, has some Events and you want to work with those Event Procedures.

When you doubleclick a control, VB autometically writes the event procedures. But, for objects declared with WithEvents, you have to write the event procedures yourself.

Take a look at the following example written by Static.

Dim WithEvents HTML As HTMLDocument
 
Private Sub Form_Load()
    WebBrowser1.Navigate "http://www.google.com"
End Sub
 
Private Function HTML_ondragstart() As Boolean
    HTML_ondragstart = False
End Function
 
 
Private Sub WebBrowser1_DocumentComplete(ByVal pDisp As Object, URL As Variant)
    If (pDisp Is WebBrowser1.Application) Then
        Set HTML = WebBrowser1.Document
    End If
End Sub

In the above example, HTML is an object and it has some events. But as it is not a control (VB will not write it autometically), and we don't have the source code.
So to trap the dragging Static has written the HTML_ondragstart event procedure manually.
So, whenever user drags a link, the drag event fires, and the code inside the event procedure will run.

More more reference see:
http://www.developer.com/net/vb/article.php/1541411
http://www.codeguru.com/columns/vb/article.php/c6557/
and your MSDN CDs.

[Hack]

Typically I will use With Events if I'm dynamically creating controls so that I can code the controls event (usually the click event) once the control has been made.

[iPrank]

@Hack,
Isn't it easier to use a control array and add the first control at designtime (Index=0) and rest of the controls at runtime ?

[Hack]

@Hack,
Isn't it easier to use a control array and add the first control at designtime (Index=0) and rest of the controls at runtime ?

Yes...but not nearly as much fun!