Items of ParamArray can be Missing

When using the ParamArray keyword within a procedure, always remember that when the procedure is invoked from elsewhere in the program one of the argument might be omitted, and you should keep this into account. Here is an example of a routine that uses ParamArray:

Function Max(ParamArray args() As Variant) As Variant  Dim result As Variant, index As Integer  result = args(LBound(args))  For index = LBound(args) + 1 To UBound(args)    If result < args(index) Then result = args(index)  Next  Max = resultEnd Function

The above routine works fine, but only if the programmer doesn't omit any argument in the list. If you recall the function as in:

Print Max(1, , 3)    

the function will raise a "Type Mismatch" error. Here's a better version, that also accounts for missing arguments:

Function Max(ParamArray args() As Variant) As Variant  Dim result As Variant, index As Integer  For index = LBound(args) To UBound(args)    If IsMissing(args(index)) Then      ' ignore this argument    ElseIf IsEmpty(result) Then      ' the first time we set a possible return value      result = args(index)    ElseIf result < args(index) Then       result = args(index)    End If  Next  Max = resultEnd Function

Also, remember that to a Variant argument you can pass almost anything, including objects and arrays. If you really want to create a general-purpose routine you should account for these cases too.

Share the Post:
Share on facebook
Share on twitter
Share on linkedin

Overview

The Latest

technology leadership

Why the World Needs More Technology Leadership

As a fact, technology has touched every single aspect of our lives. And there are some technology giants in today’s world which have been frequently opined to have a strong influence on recent overall technological influence. Moreover, those tech giants have popular technology leaders leading the companies toward achieving greatness.

iOS app development

The Future of iOS App Development: Trends to Watch

When it launched in 2008, the Apple App Store only had 500 apps available. By the first quarter of 2022, the store had about 2.18 million iOS-exclusive apps. Average monthly app releases for the platform reached 34,000 in the first half of 2022, indicating rapid growth in iOS app development.

microsoft careers

Top Careers at Microsoft

Microsoft has gained its position as one of the top companies in the world, and Microsoft careers are flourishing. This multinational company is efficiently developing popular software and computers with other consumer electronics. It is a dream come true for so many people to acquire a high paid, high-prestige job