What are non-generic collections in C#? ArrayList, Stack, Queue, Hashtable, SortedList, BitArray classes

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C# (programming language)

Что такое необобщенные коллекции в C# ?

посмотрели 16065 раз

обновлено: 25 September 2018

В необобщенной коллекции элементы могут быть разного типа.

C# Пример

// создаем ArrayList
ArrayList myList = new ArrayList();

// добавляем элементы разного типа
myList.Add(1);
myList.Add("Привет");
myList.Add(7.5);

Необобщенные коллекции это списки, словари и другие классы для добавления, удаления, сортировки элементов.

Классы необобщенных коллекций

Необобщенные коллекции определены в пространстве имен System.Collections

ArrayList

класс для добавления, удаления элементов

SortedList

класс хранящей наборы пар "ключ-значение", отсортированных по ключу

Stack

класс использует алгоритм "последний вошел - первый вышел".
Каждый добавленный элемент помещается в самый верх.
Первым извлекается элемент, который находится в самом верху стека.

Queue

класс использует алгоритм "первый вошел - первый вышел".
тоже самое что и очередь в магазине

Hashtable

класс храняющий набор пар "ключ-значение"

BitArray

класс хранящий массив битовых значений

Диаграмма наследования необобщенных коллекций

Читать: что такое интерфейс IEnumerable в C# ?...

Читать: что такое интерфейсы ICollection, IList, IDictionary в C# ?...

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What are generic (typed) collections in C#? The classes are List<T>, SortedList<T>, Stack<T>, Dictionary<TKey, TValue>, LinkedList<T>, Queue<T>, HashSet<T>, SortedSet<T>, ConcurrentDictionary<TKey, TValue>, SortedDictionary<TKey, TValue>

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SortedList class (collection in C#)

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Stack class (collection in C#)

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Queue class (collection in C#)

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Hashtable class (collection in C#)

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BitArray class (collection in C#)

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Reflection in C#

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▷

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Database in Console Application C#

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exe to C# code

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In a C# application, call the C++ functions

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• In the application C# we call functions from Windows dll (C++ WinAPI). Attribute [DllImport("user32.dll")]

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Additional topics, questions

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• Why can"t the Dictionary.TryGetValue method find a value by key in C#?

• Object-oriented programming (OOP). OOP Principles: Abstraction, Encapsulation, Inheritance, Polymorphism

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• How do I download and install the version of the .NET Framework I want in Visual Studio?

• Boxing and unboxing meaningful types in C#

• Error CS8107 Feature "default literal" is not available in C# 7.0. Please use language version 7.1 or greater

• Error "unable to connect to web server "iis express" | C# | Visual Studio 2017

• Uninstall and install NuGet in Visual Studio

• When opening a project in Visual Studio 2019 error: "project requires "SQL Server 2012 Express LocalDB" which is not installed on this computer"

The checked and unchecked math operators

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• The checked math operator in C#

Additional C# classes

• C# Random class

• C# Structure Point

• C# PointF structure

• C# Size structure

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• C# RectangleF structure

It"s time

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Encryption

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Excell

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WWW Sites to Learn C#

• Websites to learn C#

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