This short script tests a variety of Collections (using the Contains function)

test_contains.vb

Public Sub TestContains()

    'Test "primitives" collection (i.e. Strings, Longs, etc.)
    Dim colStrings As Collection
    Set colStrings = New Collection

    'Add Item / Key pairs (of strings)
    colStrings.Add Item:="Item1", Key:="Key1"
    colStrings.Add Item:="Item2", Key:="Key2"

    'Verify that the Contains function works
    Debug.Print "=== Testing Strings"
    Debug.Print Contains(colStrings, "Key1") '<~ should print True
    Debug.Print Contains(colStrings, "Key99") '<~ should print False
    Debug.Print Contains(colStrings, "Key2") '<~ should print True
    Debug.Print "=== Done Testing Strings!"



    'Test "objects" collection (i.e. Ranges, Worksheets, etc.)
    Dim colRanges As Collection
    Set colRanges = New Collection

    'Add Item / Key pairs (range / string)
    colRanges.Add Item:=Range("A1"), Key:="RangeKey1"
    colRanges.Add Item:=Range("A2"), Key:="RangeKey2"

    'Verify that the Contains function works
    Debug.Print "=== Testing Ranges"
    Debug.Print Contains(colRanges, "RangeKey1") '<~ should print True
    Debug.Print Contains(colRanges, "RangeKey3000") '<~ should print False
    Debug.Print Contains(colRanges, "RangeKey2") '<~ should print True
    Debug.Print "=== Done Testing Ranges!"



    'Test "empty" collection (i.e. no items or keys)
    Dim colEmpty As Collection
    Set colEmpty = New Collection

    'Verify that the Contains function works
    Debug.Print "=== Testing Empty"
    Debug.Print Contains(colEmpty, "AnyOldKey") '<~ should print False
    Debug.Print "=== Done Testing Empty!"



    'Test "nothing" collection (i.e. a nasty case haha)
    Dim colNothing As Collection
    Set colNothing = Nothing

    'Verify that the Contains function works
    Debug.Print "=== Testing Nothing"
    Debug.Print Contains(colEmpty, "NothingKey") '<~ should print False
    Debug.Print "=== Done Testing Nothing!"
    
    
    
    'Test "long" collection where no key is provided
    Dim colLongs As Collection
    Set colLongs = New Collection
    
    'Add Items
    colLongs.Add Item:=1
    colLongs.Add Item:=2
    
    'Verify that the Contains function works
    Debug.Print "=== Testing Longs (with no Keys)"
    Debug.Print Contains(colLongs, , 1) '<~ should print True
    Debug.Print Contains(colLongs, , 42) '<~ should print False
    Debug.Print Contains(colLongs, , 2) '<~ should print True
    Debug.Print "=== Done Testing Longs (with no Keys)!"
    
    
    
    'Test "nothing passed in" collection, where no Key or Item is passed-in
    Dim colNothingPassedIn As Collection
    Set colNothingPassedIn = New Collection
    
    'Add Items
    colNothingPassedIn.Add Item:="Test", Key:="Test"
    
    'Verify that the Contains function works
    Debug.Print "=== Testing Nothing Passed In"
    Debug.Print Contains(colNothingPassedIn) '<~ should print False
    Debug.Print "=== Done Testing Nothing Passed In!"
    
End Sub