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  • Artykuł

Dictionary<TKey, TValue> Constructor (IDictionary<TKey, TValue>, IEqualityComparer<TKey>)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Initializes a new instance of the Dictionary<TKey, TValue> class that contains elements copied from the specified IDictionary<TKey, TValue> and uses the specified IEqualityComparer<T>.

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

Syntax

'Declaration
Public Sub New ( _
    dictionary As IDictionary(Of TKey, TValue), _
    comparer As IEqualityComparer(Of TKey) _
)

public Dictionary(
    IDictionary<TKey, TValue> dictionary,
    IEqualityComparer<TKey> comparer
)

Parameters

Exceptions

Exception Condition
ArgumentNullException

dictionary is nulla null reference (Nothing in Visual Basic).
ArgumentException

dictionary contains one or more duplicate keys.

Remarks

Use this constructor with the case-insensitive string comparers provided by the StringComparer class to create dictionaries with case-insensitive string keys.

Every key in a Dictionary<TKey, TValue> must be unique according to the specified comparer; likewise, every key in the source dictionary must also be unique according to the specified comparer.

NoteNote:

For example, duplicate keys can occur if comparer is one of the case-insensitive string comparers provided by the StringComparer class and dictionary does not use a case-insensitive comparer key.

The initial capacity of the new Dictionary<TKey, TValue> is large enough to contain all the elements in dictionary.

Dictionary<TKey, TValue> requires an equality implementation to determine whether keys are equal. If comparer is nulla null reference (Nothing in Visual Basic), this constructor uses the default generic equality comparer, EqualityComparer<T>.Default. If type TKey implements the System.IEquatable<T> generic interface, the default equality comparer uses that implementation.

This constructor is an O(n) operation, where n is the number of elements in dictionary.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.