The Dictionary object stores information in name/value pairs.
Examples
Does a specified key exist?
How to create a Dictionary object, and then use the Exists method to check if a specified key exists.
Return an array of all items
How to use the Items method to return an array of all the items.
Return an array of all keys
How to use the Keys method to return an array of all the keys.
Return the value of an item
How to use the Item property to return the value of an item.
Set a key
How to use the Key property to set a key in a Dictionary object.
Return the number of key/item pairs
How to use the Count property to return the number of key/item pairs.
The Dictionary Object
The Dictionary object is used to store information in name/value pairs (referred to as key and item). The Dictionary object might seem similar to Arrays, however, the Dictionary object is a more desirable solution to manipulate related data.
Comparing Dictionaries and Arrays:
- Keys are used to identify the items in a Dictionary object
- You do not have to call ReDim to change the size of the Dictionary object
- When deleting an item from a Dictionary, the remaining items will automatically shift up
- Dictionaries cannot be multidimensional, Arrays can
- Dictionaries have more built-in functions than Arrays
- Dictionaries work better than arrays on accessing random elements frequently
- Dictionaries work better than arrays on locating items by their content
The following example creates a Dictionary object, adds some key/item pairs to it, and retrieves the item value for the key gr:
<%
Dim d
Set d=Server.CreateObject("Scripting.Dictionary")
d.Add "re","Red"
d.Add "gr","Green"
d.Add "bl","Blue"
d.Add "pi","Pink"
Response.Write("The value of key gr is: " & d.Item("gr"))
%>
Output:
The value of key gr is: Green
The Dictionary object's properties and methods are described below:
Properties
| Property | Description |
|---|---|
| CompareMode | Sets or returns the comparison mode for comparing keys in a Dictionary object |
| Count | Returns the number of key/item pairs in a Dictionary object |
| Item | Sets or returns the value of an item in a Dictionary object |
| Key | Sets a new key value for an existing key value in a Dictionary object |
Methods
| Method | Description |
|---|---|
| Add | Adds a new key/item pair to a Dictionary object |
| Exists | Returns a Boolean value that indicates whether a specified key exists in the Dictionary object |
| Items | Returns an array of all the items in a Dictionary object |
| Keys | Returns an array of all the keys in a Dictionary object |
| Remove | Removes one specified key/item pair from the Dictionary object |
| RemoveAll | Removes all the key/item pairs in the Dictionary object |