' The following code example enumerates the elements of a OrderedDictionary.
Imports System
Imports System.Collections
Imports System.Collections.Specialized
Public Class OrderedDictionarySample
Public Shared Sub Main()
' Creates and initializes a OrderedDictionary.
Dim myOrderedDictionary As New OrderedDictionary()
myOrderedDictionary.Add("testKey1", "testValue1")
myOrderedDictionary.Add("testKey2", "testValue2")
myOrderedDictionary.Add("keyToDelete", "valueToDelete")
myOrderedDictionary.Add("testKey3", "testValue3")
Dim keyCollection As ICollection = myOrderedDictionary.Keys
Dim valueCollection As ICollection = myOrderedDictionary.Values
' Display the contents Imports the key and value collections
DisplayContents( _
keyCollection, valueCollection, myOrderedDictionary.Count)
' Modifying the OrderedDictionary
If Not myOrderedDictionary.IsReadOnly Then
' Insert a new key to the beginning of the OrderedDictionary
myOrderedDictionary.Insert(0, "insertedKey1", "insertedValue1")
' Modify the value of the entry with the key "testKey2"
myOrderedDictionary("testKey2") = "modifiedValue"
' Remove the last entry from the OrderedDictionary: "testKey3"
myOrderedDictionary.RemoveAt(myOrderedDictionary.Count - 1)
' Remove the "keyToDelete" entry, if it exists
If (myOrderedDictionary.Contains("keyToDelete")) Then
myOrderedDictionary.Remove("keyToDelete")
End If
End If
Console.WriteLine( _
"{0}Displaying the entries of a modified OrderedDictionary.", _
Environment.NewLine)
DisplayContents( _
keyCollection, valueCollection, myOrderedDictionary.Count)
' Clear the OrderedDictionary and add new values
myOrderedDictionary.Clear()
myOrderedDictionary.Add("newKey1", "newValue1")
myOrderedDictionary.Add("newKey2", "newValue2")
myOrderedDictionary.Add("newKey3", "newValue3")
' Display the contents of the "new" Dictionary Imports an enumerator
Dim myEnumerator As IDictionaryEnumerator = _
myOrderedDictionary.GetEnumerator()
Console.WriteLine( _
"{0}Displaying the entries of a 'new' OrderedDictionary.", _
Environment.NewLine)
DisplayEnumerator(myEnumerator)
Console.ReadLine()
End Sub
' Displays the contents of the OrderedDictionary from its keys and values
Public Shared Sub DisplayContents( _
ByVal keyCollection As ICollection, _
ByVal valueCollection As ICollection, ByVal dictionarySize As Integer)
Dim myKeys(dictionarySize) As [String]
Dim myValues(dictionarySize) As [String]
keyCollection.CopyTo(myKeys, 0)
valueCollection.CopyTo(myValues, 0)
' Displays the contents of the OrderedDictionary
Console.WriteLine(" INDEX KEY VALUE")
Dim i As Integer
For i = 0 To dictionarySize - 1
Console.WriteLine(" {0,-5} {1,-25} {2}", _
i, myKeys(i), myValues(i))
Next i
Console.WriteLine()
End Sub
' Displays the contents of the OrderedDictionary using its enumerator
Public Shared Sub DisplayEnumerator( _
ByVal myEnumerator As IDictionaryEnumerator)
Console.WriteLine(" KEY VALUE")
While myEnumerator.MoveNext()
Console.WriteLine(" {0,-25} {1}", _
myEnumerator.Key, myEnumerator.Value)
End While
End Sub
End Class
'This code produces the following output.
'
' INDEX KEY VALUE
'0: testKey1(testValue1)
'1: testKey2(testValue2)
'2: keyToDelete(valueToDelete)
'3: testKey3(testValue3)
'
'
'Displaying the entries of a modified OrderedDictionary.
' INDEX KEY VALUE
'0: insertedKey1(insertedValue1)
'1: testKey1(testValue1)
'2: testKey2(modifiedValue)
'
'
'Displaying the entries of a "new" OrderedDictionary.
' KEY(VALUE)
' newKey1(newValue1)
' newKey2(newValue2)
' newKey3(newValue3)