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VBA / Excel/ using optional Parameters

what is wrong with this piece of code, used in VB - Excel application

Function TestOptions(i As Integer, Optional k As Integer) As Integer

If IsMissing(k) Then
TestOptions = i
Else
TestOptions = i * k
End If
End Function

Function TestOptionsStr(i As String, Optional k As String) As String

If IsMissing(k) Then
TestOptions = "one arg"
Else
TestOptions = "Two args"
End If
End Function

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mladenovicz

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mladenovicz

MSDN:

Use the IsMissing function to detect whether or not optional Variant arguments have been provided in calling a procedure. IsMissing returns True if no value has been passed for the specified argument; otherwise, it returns False. If IsMissing returns True for an argument, use of the missing argument in other code may cause a user-defined error. If IsMissing is used on a ParamArray argument, it always returns False. To detect an empty ParamArray, test to see if thearray’s upper bound is less than its lower bound.

Note IsMissing does not work on simple data types (such as Integer or Double) because, unlike Variants, they don't have a provision for a "missing" flag bit. Because of this, the syntax for typed optional arguments allows you to specify a default value. If the argument is omitted when the procedure is called, then the argument will have this default value, as in the example below:

mladenovicz

Here is the example that should be in my prev post

Sub MySub(Optional MyVar As String = "specialvalue")
If MyVar = "specialvalue" Then
' MyVar was omitted.
Else
...
End Sub

BdLm

ASKER

thanks for the help, now my pgm is running .-)