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SortedList<TKey, TValue>.IDictionary.Contains Method

Determines whether the IDictionary contains an element with the specified key.

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

bool IDictionary.Contains(
	Object key
)

Parameters

key
Type: System.Object

The key to locate in the IDictionary.

Return Value

Type: System.Boolean
true if the IDictionary contains an element with the key; otherwise, false.

Implements

IDictionary.Contains(Object)

ExceptionCondition
ArgumentNullException

key is null.

This method returns false if key is of a type that is not assignable to the key type TKey of the SortedList<TKey, TValue>.

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

The following code example shows how to use the IDictionary.Contains method of the System.Collections.IDictionary interface with a SortedList<TKey, TValue>. The example demonstrates that the method returns false if a key of the wrong data type is supplied.

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 list of strings, with string keys, 
        // and access it using the IDictionary interface. 
        //
        IDictionary openWith = new SortedList<string, string>();

        // Add some elements to the sorted list. 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));


...


    }
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0
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