Name
Hashtable.Keys Property
Class
System.Collections.Hashtable
Syntax
hashtablevariable
.Keys( )
-
hashtablevariable
Use: Required
Type: Hashtable object
A reference to a Hashtable object
Return Value
An ICollection
interface containing the keys in
the hash table
Description
Returns an ICollection
interface that contains the
keys in the hash table. There is not much we can do with an
ICollection
object except copy it to an array of
Objects using its CopyTo method, as the following example
illustrates.
Example
Dim hshStates As New Hashtable Dim iColl As ICollection Dim aKeys( ), sKey As String hshStates.Add("NY", "New York") hshStates.Add("MI", "Michigan") hshStates.Add("CA", "California") hshStates.Add("WI", "Wisconsin") hshStates.Add("VT", "Vermont") hshStates.Item("WA") = "Washington" hshStates.Item("AK") = "Alaska" Redim aKeys(hshStates.Count - 1) iColl = hshStates.Keys iColl.CopyTo(aKeys, 0) for each sKey in aKeys Console.WriteLine(hshStates.Item(sKey)) Next
Programming Tips and Gotchas
You can work around the inconvenience of calling the
ICollection
object’s CopyTo method to
convert the interface to another object by defining a class that
inherits from or implements ICollection
.
See Also
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