Name
Hashtable.Add Method
Class
System.Collections.Hashtable
Syntax
hashtablevariable
.Add(Key, Value
)
-
Key
Use: Required
Data Type: Object
The hash table entry’s key
-
Value
Use: Required
Data Type: Object
The hash table entry’s value
Return Value
None
Description
Adds a key/value pair to the hash table
Rules at a Glance
Key
must be unique or a runtime error occurs.Keys are immutable. Once added, a particular key value cannot be changed during the lifetime of the hash table except by removing it through the Remove or Clear method and then adding it once again.
Value
need not be unique.
Programming Tips and Gotchas
According to the documentation, it is better to build a key from a
String
object than the Base Class Library’sStringBuilder
object.The Item property can also be used to add new members to the hash table.
To insure that key is unique when calling the Add method, you can call the ContainsKey method beforehand.
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