Paul Vick on two new operators in VB Whidbey

In a recent post to his blog, Paul Vick discusses the new IsNot Operator (and the history/rational behind the Is operator), which allows you to write;

If myString IsNot Nothing Then

instead of

If Not myString Is Nothing Then

and then, in another post, he covers the new TryCast operator (which is like C#’s ‘as’ operator), which will allow you to save a bit of extra work (and produce a slight perf improvement in some situations) when checking to see if an object can be cast to a specific type …. allowing you to write;

Sub Print(ByVal o As Object)
    Dim PrintableObject As IPrintable _
= TryCast(o, IPrintable) If PrintableObject IsNot Nothing Then PrintableObject.Print() End If ... End Sub

instead of the slightly less efficient

Sub Print(ByVal o As Object)
    Dim PrintableObject As IPrintable
    If TypeOf o Is IPrintable Then
        PrintableObject = CType(o, IPrintable)
        PrintableObject.Print()
    End If
    ...
End Sub
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