This documentation is archived and is not being maintained.

IDictionary<TKey, TValue>::TryGetValue Method

Gets the value associated with the specified key.

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

bool TryGetValue(
	TKey key, 
	[OutAttribute] TValue% value
)

Parameters

key
Type: TKey

The key whose value to get.

value
Type: TValue%

When this method returns, the value associated with the specified key, if the key is found; otherwise, the default value for the type of the value parameter. This parameter is passed uninitialized.

Return Value

Type: System::Boolean
true if the object that implements IDictionary<TKey, TValue> contains an element with the specified key; otherwise, false.

ExceptionCondition
ArgumentNullException

key is nullptr.

This method combines the functionality of the ContainsKey method and the Item property.

If the key is not found, then the value parameter gets the appropriate default value for the value type V; for example, zero (0) for integer types, false for Boolean types, and nullptr for reference types.

The example shows how to use the TryGetValue method to retrieve values. If a program frequently tries key values that are not in a dictionary, the TryGetValue method can be more efficient than using the Item property (the indexer in C#), which throws exceptions when attempting to retrieve nonexistent keys.

This code is part of a larger example that can be compiled and executed. See System.Collections.Generic::IDictionary<TKey, TValue>.

No code example is currently available or this language may not be supported.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0

.NET Compact Framework

Supported in: 3.5, 2.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
Show: