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Dictionary<TKey,TValue>.IDictionary.Values Property

Definition

Gets an ICollection containing the values in the IDictionary.

property System::Collections::ICollection ^ System::Collections::IDictionary::Values { System::Collections::ICollection ^ get(); };
System.Collections.ICollection System.Collections.IDictionary.Values { get; }
member this.System.Collections.IDictionary.Values : System.Collections.ICollection
 ReadOnly Property Values As ICollection Implements IDictionary.Values

Property Value

An ICollection containing the values in the IDictionary.

Implements

Examples

The following code example shows how to use the IDictionary.Values property of the System.Collections.IDictionary interface with a Dictionary<TKey,TValue>, to list the values in the dictionary. The example also shows how to enumerate the key/value pairs in the dictionary; note that the enumerator for the System.Collections.IDictionary interface returns DictionaryEntry objects rather than KeyValuePair<TKey,TValue> objects.

The code example is part of a larger example, including output, provided for the IDictionary.Add method.

using System;
using System.Collections;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        // Create a new dictionary of strings, with string keys,
        // and access it using the IDictionary interface.
        //
        IDictionary openWith = new Dictionary<string, string>();

        // Add some elements to the dictionary. There are no
        // duplicate keys, but some of the values are duplicates.
        // IDictionary.Add throws an exception if incorrect types
        // are supplied for key or value.
        openWith.Add("txt", "notepad.exe");
        openWith.Add("bmp", "paint.exe");
        openWith.Add("dib", "paint.exe");
        openWith.Add("rtf", "wordpad.exe");
open System
open System.Collections
open System.Collections.Generic

// Create a new dictionary of strings, with string keys,
// and access it using the IDictionary interface.
let openWith: IDictionary = Dictionary<string, string>()

// Add some elements to the dictionary. There are no
// duplicate keys, but some of the values are duplicates.
// IDictionary.Add throws an exception if incorrect types
// are supplied for key or value.
openWith.Add("txt", "notepad.exe")
openWith.Add("bmp", "paint.exe")
openWith.Add("dib", "paint.exe")
openWith.Add("rtf", "wordpad.exe")
Imports System.Collections
Imports System.Collections.Generic

Public Class Example
    
    Public Shared Sub Main() 

        ' Create a new dictionary of strings, with string keys,
        ' and access it using the IDictionary interface.
        '
        Dim openWith As IDictionary = _
            New Dictionary(Of String, String)
        
        ' Add some elements to the dictionary. There are no 
        ' duplicate keys, but some of the values are duplicates.
        ' IDictionary.Add throws an exception if incorrect types
        ' are supplied for key or value.
        openWith.Add("txt", "notepad.exe")
        openWith.Add("bmp", "paint.exe")
        openWith.Add("dib", "paint.exe")
        openWith.Add("rtf", "wordpad.exe")
// To get the values alone, use the Values property.
ICollection icoll = openWith.Values;

// The elements of the collection are strongly typed
// with the type that was specified for dictionary values,
// even though the ICollection interface is not strongly
// typed.
Console.WriteLine();
foreach( string s in icoll )
{
    Console.WriteLine("Value = {0}", s);
}
// To get the values alone, use the Values property.
let icoll: ICollection = openWith.Values

// The elements of the collection are strongly typed
// with the type that was specified for dictionary values,
// even though the ICollection interface is not strongly
// typed.
printfn ""

for s in icoll do
    printfn $"Value = {s}"
' To get the values alone, use the Values property.
Dim icoll As ICollection = openWith.Values

' The elements of the collection are strongly typed
' with the type that was specified for dictionary values,
' even though the ICollection interface is not strongly
' typed.
Console.WriteLine()
For Each s As String In  icoll
    Console.WriteLine("Value = {0}", s)
Next s
// When you use foreach to enumerate dictionary elements
// with the IDictionary interface, the elements are retrieved
// as DictionaryEntry objects instead of KeyValuePair objects.
Console.WriteLine();
foreach( DictionaryEntry de in openWith )
{
    Console.WriteLine("Key = {0}, Value = {1}",
        de.Key, de.Value);
}
// When you use foreach to enumerate dictionary elements
// with the IDictionary interface, the elements are retrieved
// as DictionaryEntry objects instead of KeyValuePair objects.
printfn ""

for de in openWith do
    let de = de :?> DictionaryEntry
    printfn $"For key = {de.Key}, value = {de.Value}"
' When you use foreach to enumerate dictionary elements
' with the IDictionary interface, the elements are retrieved
' as DictionaryEntry objects instead of KeyValuePair objects.
Console.WriteLine()
For Each de As DictionaryEntry In openWith
    Console.WriteLine("Key = {0}, Value = {1}", _
        de.Key, de.Value)
Next
    }
}

    End Sub

End Class

Remarks

The order of the values in the returned ICollection is unspecified, but it is guaranteed to be the same order as the corresponding keys in the ICollection returned by the Keys property.

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

Applies to

See also