System.Collections.Generic.Stack<T> Class

Table of Contents

• Constructors
• Properties
• Methods
• Examples

Constructors

• public Stack<T>()

  Initializes a new instance of the Stack<T> class that is empty, has the default initial capacity, and uses the reference equality comparer for the list type.

• public Stack<T>(int capacity)

  Initializes a new instance of the Stack<T> class that is empty, has the specified initial capacity, and uses the reference equality comparer for the list type.

  Parameters:

  • capacity: The number of elements that the new stack can initially hold.

Properties

• public int Count { get; }

  Gets the number of elements contained in the Stack<T>.

Methods

• public void Push(T item)

  Inserts an item at the top of the Stack<T>.

  Parameters:

  • item: The item to push onto the Stack<T>. The value can be null for reference types.
• public T Pop()

  Removes and returns the object at the top of the Stack<T>.

  Returns:

  The object removed from the top of the Stack<T>.

  Exceptions:

  • InvalidOperationException: The Stack<T> is empty.
• public T Peek()

  Returns the object at the top of the Stack<T> without removing it.

  Returns:

  The object at the top of the Stack<T>.

  Exceptions:

  • InvalidOperationException: The Stack<T> is empty.
• public bool Contains(T item)

  Determines whether an element is in the Stack<T>.

  Parameters:

  • item: The item to locate in the Stack<T>. The value can be null for reference types.

  Returns:

  true if item is found in the Stack<T>; otherwise, false.

• public void Clear()

  Removes all objects from the Stack<T>.

Examples

using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        // Create a new stack of strings
        Stack<string> myStack = new Stack<string>();

        // Push elements onto the stack
        myStack.Push("Apple");
        myStack.Push("Banana");
        myStack.Push("Cherry");

        // Get the number of elements
        Console.WriteLine($"Stack count: {myStack.Count}"); // Output: Stack count: 3

        // Peek at the top element
        Console.WriteLine($"Top element: {myStack.Peek()}"); // Output: Top element: Cherry

        // Pop elements from the stack
        while (myStack.Count > 0)
        {
            string item = myStack.Pop();
            Console.WriteLine($"Popped: {item}");
        }
        // Output:
        // Popped: Cherry
        // Popped: Banana
        // Popped: Apple

        // Check if stack is empty
        Console.WriteLine($"Stack is empty: {myStack.Count == 0}"); // Output: Stack is empty: True
    }
}