Name
Hashtable.Item Property
Class
System.Collections.Hashtable
Syntax
hashtablevariable
.Item(key
)
-
hashtablevariable
Use: Required
Type: Hashtable object
A reference to a Hashtable object
-
key
Use: Required
Data Type: Object
The key whose value is to be retrieved
Return Value
An Object representing the value associated with
key
Description
Returns an Object that is the value associated with a particular key/value pair.
Rules at a Glance
Item is the default property of the
Hashtable
object, and since it is parameterized, we can write:hashtablevariable(key)
Item is a read/write property. In other words, you can use the Item property to retrieve the value belonging to a particular key, as well as to modify the value belonging to a particular key.
If
key
does not exist in the hash table when you attempt to retrieve a value, the Item property returnsNothing
.If
key
does not exist in the hash table when you attempt to modify a value, the key and its associated value are added to the hash table, as a sort of implicit add. For example, if the key"AK"
does not exist in a hash table, the code fragment:hshStates.Item("AK") = "Alaska"
adds the key
"AK"
and its associated value,"Alaska"
.
Programming Tips and Gotchas
To guard against inadvertently adding a member to the hash table when you intend to modify an existing value, call the ContainsKey method beforehand.
You can also retrieve individual members of the
Hashtable
object by iterating it using theFor
Each...Next
statement. Each iteration of the ...
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