SortedDictionary<TKey, TValue> Constructor ()

 

Initializes a new instance of the SortedDictionary<TKey, TValue> class that is empty and uses the default IComparer<T> implementation for the key type.

Namespace:   System.Collections.Generic
Assembly:  System (in System.dll)

public SortedDictionary()

Every key in a SortedDictionary<TKey, TValue> must be unique according to the default comparer.

SortedDictionary<TKey, TValue> requires a comparer implementation to perform key comparisons. This constructor uses the default generic equality comparer Comparer<T>.Default. If type TKey implements the System.IComparable<T> generic interface, the default comparer uses that implementation. Alternatively, you can specify an implementation of the IComparer<T> generic interface by using a constructor that accepts a comparer parameter.

This constructor is an O(1) operation.

The following code example creates an empty SortedDictionary<TKey, TValue> of strings with string keys and uses the Add method to add some elements. The example demonstrates that the Add method throws an ArgumentException when attempting to add a duplicate key.

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

// Create a new sorted dictionary of strings, with string
// keys.
SortedDictionary<string, string> openWith = 
    new SortedDictionary<string, string>();

// Add some elements to the dictionary. 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");

// The Add method throws an exception if the new key is 
// already in the dictionary.
try
{
    openWith.Add("txt", "winword.exe");
}
catch (ArgumentException)
{
    Console.WriteLine("An element with Key = \"txt\" already exists.");
}

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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