KeyValuePair<TKey, TValue> Structure

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

The foreach statement of the C# language (for each in C++, For Each in Visual Basic) requires 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);
}

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

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);
}

.NET Framework

.NET Framework Client Profile

Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference