DictionaryEntry DictionaryEntry DictionaryEntry DictionaryEntry Struct

Definition

Defines a dictionary key/value pair that can be set or retrieved.

public value class DictionaryEntry
[System.Runtime.InteropServices.ComVisible(true)]
[Serializable]
public struct DictionaryEntry
type DictionaryEntry = struct
Public Structure DictionaryEntry
Inheritance
DictionaryEntryDictionaryEntryDictionaryEntryDictionaryEntry
Attributes
ComVisibleAttribute SerializableAttribute

Examples

The following example demonstrates the use of DictionaryEntry to iterate through a Hashtable object.

// A simple example for the DictionaryEntry structure.
using namespace System;
using namespace System::Collections;

public ref class Example
{
public:
    static void Main()
    {
        // Create a new hash table.
        //
        Hashtable^ openWith = gcnew Hashtable();

        // Add some elements to the hash table. There are no
        // duplicate keys, but some of the values are duplicates.
        openWith->Add("txt", "notepad.exe");
        openWith->Add("bmp", "paint.exe");
        openWith->Add("dib", "paint.exe");
        openWith->Add("rtf", "wordpad.exe");

        // When you use foreach to enumerate hash table elements,
        // the elements are retrieved as DictionaryEntry objects.
        Console::WriteLine();
        for each (DictionaryEntry de in openWith)
        {
            Console::WriteLine("Key = {0}, Value = {1}", de.Key, de.Value);
        }
    }
};

int main()
{
    Example::Main();
}

/* This code example produces output similar to the following:

Key = rtf, Value = wordpad.exe
Key = txt, Value = notepad.exe
Key = dib, Value = paint.exe
Key = bmp, Value = paint.exe
 */
// A simple example for the DictionaryEntry structure.
using System;
using System.Collections;

class Example
{
    public static void Main()
    {
        // Create a new hash table.
        //
        Hashtable openWith = new Hashtable();

        // Add some elements to the hash table. There are no 
        // duplicate keys, but some of the values are duplicates.
        openWith.Add("txt", "notepad.exe");
        openWith.Add("bmp", "paint.exe");
        openWith.Add("dib", "paint.exe");
        openWith.Add("rtf", "wordpad.exe");

        // When you use foreach to enumerate hash table elements,
        // the elements are retrieved as DictionaryEntry objects.
        Console.WriteLine();
        foreach (DictionaryEntry de in openWith)
        {
            Console.WriteLine("Key = {0}, Value = {1}", de.Key, de.Value);
        }
    }
}

/* This code example produces output similar to the following:

Key = rtf, Value = wordpad.exe
Key = txt, Value = notepad.exe
Key = dib, Value = paint.exe
Key = bmp, Value = paint.exe
 */
'A simple example for the DictionaryEntry structure.
Imports System
Imports System.Collections
Imports Microsoft.VisualBasic

Module Example

    Sub Main()

        ' Create a new hash table.
        '
        Dim openWith As New Hashtable()

        ' Add some elements to the hash table. There are no
        ' duplicate keys, but some of the values are duplicates.
        openWith.Add("txt", "notepad.exe")
        openWith.Add("bmp", "paint.exe")
        openWith.Add("dib", "paint.exe")
        openWith.Add("rtf", "wordpad.exe")

        ' When you use For Each to enumerate hash table elements,
        ' the elements are retrieved as DictionaryEntry objects.
        Console.WriteLine()
        For Each de As DictionaryEntry In openWith
            Console.WriteLine("Key = {0}, Value = {1}", _
                de.Key, de.Value)
        Next de

    End Sub

End Module

' This code example produces output similar to the following:
'
'Key = rtf, Value = wordpad.exe
'Key = txt, Value = notepad.exe
'Key = dib, Value = paint.exe
'Key = bmp, Value = paint.exe

Remarks

The IDictionaryEnumerator.Entry method returns an instance of this type.

The foreach statement of the C# language (for each in Visual C++, For Each in Visual Basic) requires the type of each element in the collection. Since each element of the IDictionary is a key/value pair, the element type is not the type of the key or the type of the value. Instead, the element type is DictionaryEntry. For example:

for each (DictionaryEntry de in openWith)
{
    Console::WriteLine("Key = {0}, Value = {1}", de.Key, de.Value);
}
foreach (DictionaryEntry de in openWith)
{
    Console.WriteLine("Key = {0}, Value = {1}", de.Key, de.Value);
}
For Each de As DictionaryEntry In openWith
    Console.WriteLine("Key = {0}, Value = {1}", _
        de.Key, de.Value)
Next de

The foreach statement is a wrapper around the enumerator, which only allows reading from, not writing to, the collection.

Constructors

DictionaryEntry(Object, Object) DictionaryEntry(Object, Object) DictionaryEntry(Object, Object) DictionaryEntry(Object, Object)

Initializes an instance of the DictionaryEntry type with the specified key and value.

Properties

Key Key Key Key

Gets or sets the key in the key/value pair.

Value Value Value Value

Gets or sets the value in the key/value pair.

Methods

Deconstruct(Object, Object) Deconstruct(Object, Object) Deconstruct(Object, Object) Deconstruct(Object, Object)

Applies to

See Also