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SortedDictionary<TKey,TValue>.Add(TKey, TValue) Method

  • Reference

Definition

Namespace:
System.Collections.Generic
Assembly:
System.Collections.dll
Assembly:
System.dll
Assembly:
netstandard.dll
Source:
SortedDictionary.cs
Source:
SortedDictionary.cs
Source:
SortedDictionary.cs

Adds an element with the specified key and value into the SortedDictionary<TKey,TValue>.

public:
 virtual void Add(TKey key, TValue value);
public void Add (TKey key, TValue value);
abstract member Add : 'Key * 'Value -> unit
override this.Add : 'Key * 'Value -> unit
Public Sub Add (key As TKey, value As TValue)

Parameters

key
TKey

The key of the element to add.

value
TValue

The value of the element to add. The value can be null for reference types.

Implements

Add(TKey, TValue)

Exceptions

ArgumentNullException

key is null.

ArgumentException

An element with the same key already exists in the SortedDictionary<TKey,TValue>.

Examples

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.");
}

' Create a new sorted dictionary of strings, with string 
' keys. 
Dim openWith As New SortedDictionary(Of 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 
    Console.WriteLine("An element with Key = ""txt"" already exists.")
End Try

Remarks

You can also use the Item[] property to add new elements by setting the value of a key that does not exist in the SortedDictionary<TKey,TValue>; for example, myCollection["myNonexistentKey"] = myValue (in Visual Basic, myCollection("myNonexistantKey") = myValue). However, if the specified key already exists in the SortedDictionary<TKey,TValue>, setting the Item[] property overwrites the old value. In contrast, the Add method throws an exception if an element with the specified key already exists.

A key cannot be null, but a value can be, if the value type TValue is a reference type.

This method is an O(log n) operation, where n is Count.

Applies to

See also