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KeyValuePair<TKey,TValue> Struct

Definition

Namespace:
System.Collections.Generic
Assemblies:
mscorlib.dll, System.Runtime.dll
Assemblies:
netstandard.dll, System.Runtime.dll
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Source:
KeyValuePair.cs
Source:
KeyValuePair.cs
Source:
KeyValuePair.cs
Source:
KeyValuePair.cs
Source:
KeyValuePair.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

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

generic <typename TKey, typename TValue>
public value class KeyValuePair
public struct KeyValuePair<TKey,TValue>
public readonly struct KeyValuePair<TKey,TValue>
[System.Serializable]
public struct KeyValuePair<TKey,TValue>
type KeyValuePair<'Key, 'Value> = struct
[<System.Serializable>]
type KeyValuePair<'Key, 'Value> = struct
Public Structure KeyValuePair(Of TKey, TValue)

Type Parameters

TKey

The type of the key.

TValue

The type of the value.

Inheritance
KeyValuePair<TKey,TValue>
Attributes

Examples

The following code example shows how to enumerate the keys and values in a dictionary, using the KeyValuePair<TKey,TValue> structure.

This code is part of a larger example provided for the Dictionary<TKey,TValue> class.

// When you use foreach to enumerate dictionary elements,
// the elements are retrieved as KeyValuePair objects.
Console.WriteLine();
foreach( KeyValuePair<string, string> kvp in openWith )
{
 Console.WriteLine("Key = {0}, Value = {1}",
 kvp.Key, kvp.Value);
}

' When you use foreach to enumerate dictionary elements,
' the elements are retrieved as KeyValuePair objects.
Console.WriteLine()
For Each kvp As KeyValuePair(Of String, String) In openWith
 Console.WriteLine("Key = {0}, Value = {1}", _
 kvp.Key, kvp.Value)
Next kvp

Remarks

The Dictionary<TKey,TValue>.Enumerator.Current property returns an instance of this type.

The foreach statement of the C# language (For Each in Visual Basic) returns an object of the type of the elements in the collection. Since each element of a collection based on IDictionary<TKey,TValue> 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 KeyValuePair<TKey,TValue>. For example:

foreach( KeyValuePair<string, string> kvp in myDictionary )
{
 Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value);
}

For Each kvp As KeyValuePair(Of String, String) In myDictionary
 Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value)
Next kvp

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

Constructors

Name Description
KeyValuePair<TKey,TValue>(TKey, TValue)

Initializes a new instance of the KeyValuePair<TKey,TValue> structure with the specified key and value.

Properties

Name Description
Key

Gets the key in the key/value pair.
Value

Gets the value in the key/value pair.

Methods

Name Description
Deconstruct(TKey, TValue)

Deconstructs the current KeyValuePair<TKey,TValue>.
ToString()

Returns a string representation of the KeyValuePair<TKey,TValue>, using the string representations of the key and value.

Applies to

See also

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