Visual Basic 2005 in a Nutshell, Third Edition

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Chapter 12: The Language Reference

This is the Title of the Book, eMatter Edition

Copyright © 2006 O’Reilly & Associates, Inc. All rights reserved.

Example

The sample code copies hashtable pairs to an array.

Dim nameTable As New Hashtable

Dim stateArray( ) As DictionaryEntry

' ----- Build the hashtable.

nameTable.Add("Ch", "Chopin")

nameTable.Add("Mo", "Mozart")

nameTable.Add("Be", "Beethoven")

ReDim stateArray(nameTable.Count - 1)

nameTable.CopyTo(stateArray, 0)

See Also

Hashtable Class, Hashtable.Keys Property

Hashtable.Item Property

Class

System.Collections.Hashtable

Syntax

Dim result As Object = hashtableVariable.Item(key)

key (required; any)

The key with the related value that is to be retrieved

Description

The Item property returns the hashtable value associated with a particular key.

Usage at a Glance

• Item is the default property of the Hashtable class, so “.Item” is optional. The

following two lines are equivalent.

resultObject = myHashtable.Item("abc")

resultObject = myHashtable("abc")

• The Item property can be used to add or update values. The statement:

myHashtable.Item("abc") = sourceObject

either updates the value associated with the key “abc” (if it already exists in the

hashtable) or adds it as a new item with the key “abc” (if it does not yet exist in

the hashtable).

•If

key does not exist in the hashtable when you attempt to retrieve a value, the

Item property returns

Nothing.

• To guard