DictionaryBase.Dictionary Property

protected:
 property System::Collections::IDictionary ^ Dictionary { System::Collections::IDictionary ^ get(); };

protected System.Collections.IDictionary Dictionary { get; }

member this.Dictionary : System.Collections.IDictionary

Protected ReadOnly Property Dictionary As IDictionary

Property Value

An IDictionary representing the DictionaryBase instance itself.

Examples

The following code example implements the DictionaryBase class and uses that implementation to create a dictionary of String keys and values that have a Length of 5 characters or less.

using System;
using System.Collections;

public class ShortStringDictionary : DictionaryBase {

 public String this[ String key ] {
 get {
 return( (String) Dictionary[key] );
 }
 set {
 Dictionary[key] = value;
 }
 }

 public ICollection Keys {
 get {
 return( Dictionary.Keys );
 }
 }

 public ICollection Values {
 get {
 return( Dictionary.Values );
 }
 }

 public void Add( String key, String value ) {
 Dictionary.Add( key, value );
 }

 public bool Contains( String key ) {
 return( Dictionary.Contains( key ) );
 }

 public void Remove( String key ) {
 Dictionary.Remove( key );
 }

 protected override void OnInsert( Object key, Object value ) {
 if ( key.GetType() != typeof(System.String) )
 {
 throw new ArgumentException( "key must be of type String.", "key" );
 }
 else {
 String strKey = (String) key;
 if ( strKey.Length > 5 )
 throw new ArgumentException( "key must be no more than 5 characters in length.", "key" );
 }

 if ( value.GetType() != typeof(System.String) )
 {
 throw new ArgumentException( "value must be of type String.", "value" );
 }
 else {
 String strValue = (String) value;
 if ( strValue.Length > 5 )
 throw new ArgumentException( "value must be no more than 5 characters in length.", "value" );
 }
 }

 protected override void OnRemove( Object key, Object value ) {
 if ( key.GetType() != typeof(System.String) )
 {
 throw new ArgumentException( "key must be of type String.", "key" );
 }
 else {
 String strKey = (String) key;
 if ( strKey.Length > 5 )
 throw new ArgumentException( "key must be no more than 5 characters in length.", "key" );
 }
 }

 protected override void OnSet( Object key, Object oldValue, Object newValue ) {
 if ( key.GetType() != typeof(System.String) )
 {
 throw new ArgumentException( "key must be of type String.", "key" );
 }
 else {
 String strKey = (String) key;
 if ( strKey.Length > 5 )
 throw new ArgumentException( "key must be no more than 5 characters in length.", "key" );
 }

 if ( newValue.GetType() != typeof(System.String) )
 {
 throw new ArgumentException( "newValue must be of type String.", "newValue" );
 }
 else {
 String strValue = (String) newValue;
 if ( strValue.Length > 5 )
 throw new ArgumentException( "newValue must be no more than 5 characters in length.", "newValue" );
 }
 }

 protected override void OnValidate( Object key, Object value ) {
 if ( key.GetType() != typeof(System.String) )
 {
 throw new ArgumentException( "key must be of type String.", "key" );
 }
 else {
 String strKey = (String) key;
 if ( strKey.Length > 5 )
 throw new ArgumentException( "key must be no more than 5 characters in length.", "key" );
 }

 if ( value.GetType() != typeof(System.String) )
 {
 throw new ArgumentException( "value must be of type String.", "value" );
 }
 else {
 String strValue = (String) value;
 if ( strValue.Length > 5 )
 throw new ArgumentException( "value must be no more than 5 characters in length.", "value" );
 }
 }
}

public class SamplesDictionaryBase {

 public static void Main() {

 // Creates and initializes a new DictionaryBase.
 ShortStringDictionary mySSC = new ShortStringDictionary();

 // Adds elements to the collection.
 mySSC.Add( "One", "a" );
 mySSC.Add( "Two", "ab" );
 mySSC.Add( "Three", "abc" );
 mySSC.Add( "Four", "abcd" );
 mySSC.Add( "Five", "abcde" );

 // Display the contents of the collection using foreach. This is the preferred method.
 Console.WriteLine( "Contents of the collection (using foreach):" );
 PrintKeysAndValues1( mySSC );

 // Display the contents of the collection using the enumerator.
 Console.WriteLine( "Contents of the collection (using enumerator):" );
 PrintKeysAndValues2( mySSC );

 // Display the contents of the collection using the Keys property and the Item property.
 Console.WriteLine( "Initial contents of the collection (using Keys and Item):" );
 PrintKeysAndValues3( mySSC );

 // Tries to add a value that is too long.
 try {
 mySSC.Add( "Ten", "abcdefghij" );
 }
 catch ( ArgumentException e ) {
 Console.WriteLine( e.ToString() );
 }

 // Tries to add a key that is too long.
 try {
 mySSC.Add( "Eleven", "ijk" );
 }
 catch ( ArgumentException e ) {
 Console.WriteLine( e.ToString() );
 }

 Console.WriteLine();

 // Searches the collection with Contains.
 Console.WriteLine( "Contains \"Three\": {0}", mySSC.Contains( "Three" ) );
 Console.WriteLine( "Contains \"Twelve\": {0}", mySSC.Contains( "Twelve" ) );
 Console.WriteLine();

 // Removes an element from the collection.
 mySSC.Remove( "Two" );

 // Displays the contents of the collection.
 Console.WriteLine( "After removing \"Two\":" );
 PrintKeysAndValues1( mySSC );
 }

 // Uses the foreach statement which hides the complexity of the enumerator.
 // NOTE: The foreach statement is the preferred way of enumerating the contents of a collection.
 public static void PrintKeysAndValues1( ShortStringDictionary myCol ) {
 foreach ( DictionaryEntry myDE in myCol )
 Console.WriteLine( " {0,-5} : {1}", myDE.Key, myDE.Value );
 Console.WriteLine();
 }

 // Uses the enumerator.
 // NOTE: The foreach statement is the preferred way of enumerating the contents of a collection.
 public static void PrintKeysAndValues2( ShortStringDictionary myCol ) {
 DictionaryEntry myDE;
 System.Collections.IEnumerator myEnumerator = myCol.GetEnumerator();
 while ( myEnumerator.MoveNext() )
 if ( myEnumerator.Current != null ) {
 myDE = (DictionaryEntry) myEnumerator.Current;
 Console.WriteLine( " {0,-5} : {1}", myDE.Key, myDE.Value );
 }
 Console.WriteLine();
 }

 // Uses the Keys property and the Item property.
 public static void PrintKeysAndValues3( ShortStringDictionary myCol ) {
 ICollection myKeys = myCol.Keys;
 foreach ( String k in myKeys )
 Console.WriteLine( " {0,-5} : {1}", k, myCol[k] );
 Console.WriteLine();
 }
}


/*
This code produces the following output.

Contents of the collection (using foreach):
 Three : abc
 Five : abcde
 Two : ab
 One : a
 Four : abcd

Contents of the collection (using enumerator):
 Three : abc
 Five : abcde
 Two : ab
 One : a
 Four : abcd

Initial contents of the collection (using Keys and Item):
 Three : abc
 Five : abcde
 Two : ab
 One : a
 Four : abcd

System.ArgumentException: value must be no more than 5 characters in length.
Parameter name: value
 at ShortStringDictionary.OnValidate(Object key, Object value)
 at System.Collections.DictionaryBase.System.Collections.IDictionary.Add(Object key, Object value)
 at SamplesDictionaryBase.Main()
System.ArgumentException: key must be no more than 5 characters in length.
Parameter name: key
 at ShortStringDictionary.OnValidate(Object key, Object value)
 at System.Collections.DictionaryBase.System.Collections.IDictionary.Add(Object key, Object value)
 at SamplesDictionaryBase.Main()

Contains "Three": True
Contains "Twelve": False

After removing "Two":
 Three : abc
 Five : abcde
 One : a
 Four : abcd

*/

Imports System.Collections

Public Class ShortStringDictionary
 Inherits DictionaryBase

 Default Public Property Item(key As String) As String
 Get
 Return CType(Dictionary(key), String)
 End Get
 Set
 Dictionary(key) = value
 End Set
 End Property

 Public ReadOnly Property Keys() As ICollection
 Get
 Return Dictionary.Keys
 End Get
 End Property

 Public ReadOnly Property Values() As ICollection
 Get
 Return Dictionary.Values
 End Get
 End Property

 Public Sub Add(key As String, value As String)
 Dictionary.Add(key, value)
 End Sub

 Public Function Contains(key As String) As Boolean
 Return Dictionary.Contains(key)
 End Function 'Contains

 Public Sub Remove(key As String)
 Dictionary.Remove(key)
 End Sub

 Protected Overrides Sub OnInsert(key As Object, value As Object)
 If Not GetType(System.String).IsAssignableFrom(key.GetType()) Then
 Throw New ArgumentException("key must be of type String.", "key")
 Else
 Dim strKey As String = CType(key, String)
 If strKey.Length > 5 Then
 Throw New ArgumentException("key must be no more than 5 characters in length.", "key")
 End If
 End If 
 If Not GetType(System.String).IsAssignableFrom(value.GetType()) Then
 Throw New ArgumentException("value must be of type String.", "value")
 Else
 Dim strValue As String = CType(value, String)
 If strValue.Length > 5 Then
 Throw New ArgumentException("value must be no more than 5 characters in length.", "value")
 End If
 End If
 End Sub

 Protected Overrides Sub OnRemove(key As Object, value As Object)
 If Not GetType(System.String).IsAssignableFrom(key.GetType()) Then
 Throw New ArgumentException("key must be of type String.", "key")
 Else
 Dim strKey As String = CType(key, String)
 If strKey.Length > 5 Then
 Throw New ArgumentException("key must be no more than 5 characters in length.", "key")
 End If
 End If
 End Sub

 Protected Overrides Sub OnSet(key As Object, oldValue As Object, newValue As Object)
 If Not GetType(System.String).IsAssignableFrom(key.GetType()) Then
 Throw New ArgumentException("key must be of type String.", "key")
 Else
 Dim strKey As String = CType(key, String)
 If strKey.Length > 5 Then
 Throw New ArgumentException("key must be no more than 5 characters in length.", "key")
 End If
 End If 
 If Not GetType(System.String).IsAssignableFrom(newValue.GetType()) Then
 Throw New ArgumentException("newValue must be of type String.", "newValue")
 Else
 Dim strValue As String = CType(newValue, String)
 If strValue.Length > 5 Then
 Throw New ArgumentException("newValue must be no more than 5 characters in length.", "newValue")
 End If
 End If
 End Sub

 Protected Overrides Sub OnValidate(key As Object, value As Object)
 If Not GetType(System.String).IsAssignableFrom(key.GetType()) Then
 Throw New ArgumentException("key must be of type String.", "key")
 Else
 Dim strKey As String = CType(key, String)
 If strKey.Length > 5 Then
 Throw New ArgumentException("key must be no more than 5 characters in length.", "key")
 End If
 End If 
 If Not GetType(System.String).IsAssignableFrom(value.GetType()) Then
 Throw New ArgumentException("value must be of type String.", "value")
 Else
 Dim strValue As String = CType(value, String)
 If strValue.Length > 5 Then
 Throw New ArgumentException("value must be no more than 5 characters in length.", "value")
 End If
 End If
 End Sub

End Class


Public Class SamplesDictionaryBase

 Public Shared Sub Main()

 ' Creates and initializes a new DictionaryBase.
 Dim mySSC As New ShortStringDictionary()

 ' Adds elements to the collection.
 mySSC.Add("One", "a")
 mySSC.Add("Two", "ab")
 mySSC.Add("Three", "abc")
 mySSC.Add("Four", "abcd")
 mySSC.Add("Five", "abcde")

 ' Display the contents of the collection using For Each. This is the preferred method.
 Console.WriteLine("Contents of the collection (using For Each):")
 PrintKeysAndValues1(mySSC)

 ' Display the contents of the collection using the enumerator.
 Console.WriteLine("Contents of the collection (using enumerator):")
 PrintKeysAndValues2(mySSC)

 ' Display the contents of the collection using the Keys property and the Item property.
 Console.WriteLine("Initial contents of the collection (using Keys and Item):")
 PrintKeysAndValues3(mySSC)

 ' Tries to add a value that is too long.
 Try
 mySSC.Add("Ten", "abcdefghij")
 Catch e As ArgumentException
 Console.WriteLine(e.ToString())
 End Try

 ' Tries to add a key that is too long.
 Try
 mySSC.Add("Eleven", "ijk")
 Catch e As ArgumentException
 Console.WriteLine(e.ToString())
 End Try

 Console.WriteLine()

 ' Searches the collection with Contains.
 Console.WriteLine("Contains ""Three"": {0}", mySSC.Contains("Three"))
 Console.WriteLine("Contains ""Twelve"": {0}", mySSC.Contains("Twelve"))
 Console.WriteLine()

 ' Removes an element from the collection.
 mySSC.Remove("Two")

 ' Displays the contents of the collection.
 Console.WriteLine("After removing ""Two"":")
 PrintKeysAndValues1(mySSC)

 End Sub


 ' Uses the For Each statement which hides the complexity of the enumerator.
 ' NOTE: The For Each statement is the preferred way of enumerating the contents of a collection.
 Public Shared Sub PrintKeysAndValues1(myCol As ShortStringDictionary)
 Dim myDE As DictionaryEntry
 For Each myDE In myCol
 Console.WriteLine(" {0,-5} : {1}", myDE.Key, myDE.Value)
 Next myDE
 Console.WriteLine()
 End Sub


 ' Uses the enumerator. 
 ' NOTE: The For Each statement is the preferred way of enumerating the contents of a collection.
 Public Shared Sub PrintKeysAndValues2(myCol As ShortStringDictionary)
 Dim myDE As DictionaryEntry
 Dim myEnumerator As System.Collections.IEnumerator = myCol.GetEnumerator()
 While myEnumerator.MoveNext()
 If Not (myEnumerator.Current Is Nothing) Then
 myDE = CType(myEnumerator.Current, DictionaryEntry)
 Console.WriteLine(" {0,-5} : {1}", myDE.Key, myDE.Value)
 End If
 End While
 Console.WriteLine()
 End Sub


 ' Uses the Keys property and the Item property.
 Public Shared Sub PrintKeysAndValues3(myCol As ShortStringDictionary)
 Dim myKeys As ICollection = myCol.Keys
 Dim k As String
 For Each k In myKeys
 Console.WriteLine(" {0,-5} : {1}", k, myCol(k))
 Next k
 Console.WriteLine()
 End Sub

End Class


'This code produces the following output.
'
'Contents of the collection (using For Each):
' Three : abc
' Five : abcde
' Two : ab
' One : a
' Four : abcd
'
'Contents of the collection (using enumerator):
' Three : abc
' Five : abcde
' Two : ab
' One : a
' Four : abcd
'
'Initial contents of the collection (using Keys and Item):
' Three : abc
' Five : abcde
' Two : ab
' One : a
' Four : abcd
'
'System.ArgumentException: value must be no more than 5 characters in length.
'Parameter name: value
' at ShortStringDictionary.OnValidate(Object key, Object value)
' at System.Collections.DictionaryBase.System.Collections.IDictionary.Add(Object key, Object value)
' at SamplesDictionaryBase.Main()
'System.ArgumentException: key must be no more than 5 characters in length.
'Parameter name: key
' at ShortStringDictionary.OnValidate(Object key, Object value)
' at System.Collections.DictionaryBase.System.Collections.IDictionary.Add(Object key, Object value)
' at SamplesDictionaryBase.Main()
'
'Contains "Three": True
'Contains "Twelve": False
'
'After removing "Two":
' Three : abc
' Five : abcde
' One : a
' Four : abcd

Remarks

The On* methods are invoked only on the instance returned by the Dictionary property, but not on the instance returned by the InnerHashtable property.

Retrieving the value of this property is an O(1) operation.