Visual Basic . NET

[Grok]

VB.NET makes such prettier code than VB6.

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               'see if document has correct properties
               Dim kfDoc As AKO32.CDocument = New AKO32.CDocument
               kfDoc.hKGI = KGI
               kfDoc.OpenDocument(Doc.docid)
               Dim result As Integer = 0
               result = IIf(Len(Doc.title) = 0, 0, Math.Abs([String].Compare(Doc.title, kfDoc.Title)))
               result += IIf(Len(Doc.person) = 0, 0, Math.Abs([String].Compare(Doc.person, kfDoc.Person)))
               result += IIf(Len(Doc.type) = 0, 0, Math.Abs([String].Compare(Doc.type, kfDoc.UserType)))
               result += IIf(Len(Doc.kfdate) = 0, 0, Math.Abs([String].Compare(Doc.kfdate, kfDoc.DateCreated)))
               result += IIf(Len(Doc.description) = 0, 0, Math.Abs([String].Compare(Doc.description, kfDoc.Description)))
               result += IIf(Len(Doc.kfgroup) = 0, 0, Math.Abs([String].Compare(Doc.kfgroup, kfDoc.Group)))
               result += IIf(Len(Doc.subclass) = 0, 0, Math.Abs([String].Compare(Doc.subclass, kfDoc.Subclass)))
               If result = 0 Then      'so far so good, check keywords
                   Dim kw() As String = Split(kfDoc.UserKeywords, vbCrLf)
                   Dim lPos As Integer
                   For lPos = 1 To UBound(kw) + 1
                       Select Case lPos
                           Case 1 : result += IIf(Len(Doc.keywords1) = 0, 0, Math.Abs([String].Compare(Doc.keywords1, kw(lPos - 1))))
                           Case 2 : result += IIf(Len(Doc.keywords2) = 0, 0, Math.Abs([String].Compare(Doc.keywords2, kw(lPos - 1))))
                           Case 3 : result += IIf(Len(Doc.keywords3) = 0, 0, Math.Abs([String].Compare(Doc.keywords3, kw(lPos - 1))))
                           Case 4 : result += IIf(Len(Doc.keywords4) = 0, 0, Math.Abs([String].Compare(Doc.keywords4, kw(lPos - 1))))
                           Case 5 : result += IIf(Len(Doc.keywords5) = 0, 0, Math.Abs([String].Compare(Doc.keywords5, kw(lPos - 1))))
                           Case 6 : result += IIf(Len(Doc.keywords6) = 0, 0, Math.Abs([String].Compare(Doc.keywords6, kw(lPos - 1))))
                           Case 7 : result += IIf(Len(Doc.keywords7) = 0, 0, Math.Abs([String].Compare(Doc.keywords7, kw(lPos - 1))))
                           Case 8 : result += IIf(Len(Doc.keywords8) = 0, 0, Math.Abs([String].Compare(Doc.keywords8, kw(lPos - 1))))
                           Case 9 : result += IIf(Len(Doc.keywords9) = 0, 0, Math.Abs([String].Compare(Doc.keywords9, kw(lPos - 1))))
                       End Select
                   Next lPos
               End If

               'see if docid is contained in destination container id
               result += IIf(KGI.IsContainedIn(Doc.docid, Doc.destid), 0, 1)

               If result = 0 Then
                   'all is well, update status ...


[quasi-modo]

VB.NET makes such prettier code than VB6.

I aggree. Its the little things that have evolved in the syntax that make the codeing so much easier.

[Adron]

Did they fix the IIf operator to only evaluate one of the expressions, and did they fix boolean logic to be short-circuited?

[Banana fanna fo fanna]

VB.NET makes such prettier code than VB6.

I aggree. Its the little things that have evolved in the syntax that make the codeing so much easier.

I think he was being sarcastic.

[Grok]

Still ewwy.

As part of preparing the argument list for the call to IIf, the Visual Basic compiler calls every function in every expression.

[Adron]

And what about boolean logic?

[quasi-modo]

VB.NET makes such prettier code than VB6.

I aggree. Its the little things that have evolved in the syntax that make the codeing so much easier.

I think he was being sarcastic.

But I wasn't  

[Grok]

And what about boolean logic?

I don't know of an obvious way to test that.  Maybe

x = 0 and (side_effect_function(z))

and see if the side effect happens?

[Adron]

I don't know of an obvious way to test that.  Maybe

x = 0 and (side_effect_function(z))

and see if the side effect happens?

A typical example of when I'd want it to be short-circuited is for testing fields of a recordset like this:

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If Not IsNull(rs!field) And rs!field = "something" Then


If it is short-circuited, rs!field = "something" won't be evaluated, and you won't get a run-time error.

Another example is:

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If y <> 0 And x/y > 12 Then


[MyndFyre]

Looks like Adron's been left hanging here...

.NET evaluates boolean expressions the same way across all languages.

Your example

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If x = 0 And SideEffectFunction(z)



would not call SideEffectFunction() if x was not 0.

The example

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If Not IsNull(rs!field) And rs!field = "something" Then


would not use the comparison of rs!field to "something" if the first condition failed.

Cheers.

[Adron]

Ah, neat!

That's something that has annoyed me for a long time in VB.

[quasi-modo]

its just like any other language in any other scripting I mean if the first part of an and is false the comp just stops right there. Its the same in c++, the same in c, the same in java.

[Adron]

its just like any other language in any other scripting I mean if the first part of an and is false the comp just stops right there. Its the same in c++, the same in c, the same in java.

But different in VB.

[quasi-modo]

I dont know about vb6... but vb.net is just like the other scripting languages.

[MyndFyre]

I dont know about vb6... but vb.net is just like the other scripting languages.

uhh, no.  VB .NET is not even a scripting language!  You might be thinking of VBA (Visual Basic for Applications) or VBScript, but Visual Basic .NET is not a scripting language.

Its late binding features allow it to be used in a scripting environment, such as the dead-and-nearly-forgotten Visual Studio for Applications (Microsoft.Vsa namespace), but even that code is compiled, not interpreted.