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
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 |
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