SortedDictionary<TKey,TValue>.IDictionary.Contains(Object) Metoda

Definicja

Określa, czy IDictionary zawiera element z określonym kluczem.Determines whether the IDictionary contains an element with the specified key.

 virtual bool System.Collections.IDictionary.Contains(System::Object ^ key) = System::Collections::IDictionary::Contains;
bool IDictionary.Contains (object key);
abstract member System.Collections.IDictionary.Contains : obj -> bool
override this.System.Collections.IDictionary.Contains : obj -> bool
Function Contains (key As Object) As Boolean Implements IDictionary.Contains

Parametry

key
Object

Klucz, który ma zostać zlokalizowany w IDictionary .The key to locate in the IDictionary.

Zwraca

Boolean

true Jeśli IDictionary zawiera element z kluczem; w przeciwnym razie, false .true if the IDictionary contains an element with the key; otherwise, false.

Implementuje

Wyjątki

key to null.key is null.

Przykłady

Poniższy przykład kodu pokazuje, jak używać IDictionary.Contains metody System.Collections.IDictionary interfejsu z SortedDictionary<TKey,TValue> .The following code example shows how to use the IDictionary.Contains method of the System.Collections.IDictionary interface with a SortedDictionary<TKey,TValue>. Przykład pokazuje, że metoda zwraca, false Jeśli podano klucz nieprawidłowego typu danych.The example demonstrates that the method returns false if a key of the wrong data type is supplied.

Przykład kodu jest częścią większego przykładu, łącznie z danymi wyjściowymi dostarczonymi dla IDictionary.Add metody.The code example is part of a larger example, including output, provided for the IDictionary.Add method.

using System;
using System.Collections;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        // Create a new sorted dictionary of strings, with string keys,
        // and access it using the IDictionary interface.
        //
        IDictionary openWith = new SortedDictionary<string, string>();

        // Add some elements to the dictionary. There are no
        // duplicate keys, but some of the values are duplicates.
        // IDictionary.Add throws an exception if incorrect types
        // are supplied for key or value.
        openWith.Add("txt", "notepad.exe");
        openWith.Add("bmp", "paint.exe");
        openWith.Add("dib", "paint.exe");
        openWith.Add("rtf", "wordpad.exe");
Imports System.Collections
Imports System.Collections.Generic

Public Class Example
    
    Public Shared Sub Main() 

        ' Create a new sorted dictionary of strings, with string keys,
        ' and access it using the IDictionary interface.
        '
        Dim openWith As IDictionary = _
            New SortedDictionary(Of String, String)
        
        ' Add some elements to the dictionary. There are no 
        ' duplicate keys, but some of the values are duplicates.
        ' IDictionary.Add throws an exception if incorrect types
        ' are supplied for key or value.
        openWith.Add("txt", "notepad.exe")
        openWith.Add("bmp", "paint.exe")
        openWith.Add("dib", "paint.exe")
        openWith.Add("rtf", "wordpad.exe")
// Contains can be used to test keys before inserting
// them.
if (!openWith.Contains("ht"))
{
    openWith.Add("ht", "hypertrm.exe");
    Console.WriteLine("Value added for key = \"ht\": {0}",
        openWith["ht"]);
}

// IDictionary.Contains returns false if the wrong data
// type is supplied.
Console.WriteLine("openWith.Contains(29.7) returns {0}",
    openWith.Contains(29.7));
' Contains can be used to test keys before inserting 
' them.
If Not openWith.Contains("ht") Then
    openWith.Add("ht", "hypertrm.exe")
    Console.WriteLine("Value added for key = ""ht"": {0}", _
        openWith("ht"))
End If

' IDictionary.Contains returns False if the wrong data 
' type is supplied.
Console.WriteLine("openWith.Contains(29.7) returns {0}", _
    openWith.Contains(29.7))
    }
}

    End Sub

End Class

Uwagi

Ta metoda zwraca false wartość key , jeśli jest typu, którego nie można przypisać do typu klucza TKey SortedDictionary<TKey,TValue> .This method returns false if key is of a type that is not assignable to the key type TKey of the SortedDictionary<TKey,TValue>.

Ta metoda jest operacją O (log n ), gdzie n is Count .This method is an O(log n) operation, where n is Count.

Dotyczy