KeyCompareMode

Returns or sets the comparison mode used when matching string keys in a Collection object. Read/write.

Syntax:

  • object.KeyCompareMode
  • object.KeyCompareMode = compare
object
required An object expression that evaluates to a Collection object.
compare
A VbCompareMethod value specifying the comparison mode used by Add, Item, Remove and Exists when looking up keys.

The compare argument settings are:

Constant Value Description
vbBinaryCompare 0 Performs a case-sensitive binary comparison.
vbTextCompare 1 Performs a case-insensitive textual comparison.

Note

KeyCompareMode is a twinBASIC extension; the classic VBA Collection object always uses case-insensitive comparison and does not expose this property.

The default comparison mode is vbTextCompare, whatever the module’s Option Compare setting, so a new Collection matches keys as VBA’s does.

The mode can be changed only while the collection holds no item added with a key. Once one has been added, setting a different mode raises run-time error 5, Can’t change KeyCompareMode once keyed items have been added to the collection, and the mode stays as it was. Items added without a key do not prevent the change, and neither do keyed items that have since been removed. Setting the mode the collection already has raises no error. A compare value other than vbBinaryCompare or vbTextCompare raises run-time error 5, Invalid procedure call or argument.

Example 

Dim col As New Collection

' The default mode is text: "A" and "a" are the same key.
col.Add "first", Key:="A"
' col.Add "second", Key:="a"   ' Would raise error 457: the key is already in use.

Dim col2 As New Collection
col2.KeyCompareMode = vbBinaryCompare   ' Before any item is added with a key.
col2.Add "first", Key:="A"
col2.Add "second", Key:="a"   ' A different key from "A", so it succeeds.

See Also