Stack.ToString() Method in C# with examples

The Stack.ToString() method in C# is used to get the string representation of the Stack class object. This method returns the fully qualified type name of the stack instance, not the contents of the stack. To display stack elements, you need to iterate through the collection and call ToString() on individual elements.

Syntax

Following is the syntax for the Stack.ToString() method −

public override string ToString();

Return Value

This method returns a string that represents the current Stack object. It returns the type name "System.Collections.Stack".

Using ToString() on Stack Elements

The following example demonstrates how to use ToString() on individual stack elements while iterating through the collection −

using System;
using System.Collections;

public class Demo {
    public static void Main() {
        Stack stack = new Stack();
        stack.Push(150);
        stack.Push(300);
        stack.Push(500);
        stack.Push(750);
        stack.Push(1000);
        stack.Push(1250);
        stack.Push(1500);
        stack.Push(2000);
        stack.Push(2500);
        
        Console.WriteLine("Stack elements...");
        foreach(int val in stack) {
            Console.WriteLine(val.ToString());
        }
        Console.WriteLine("Count of elements = " + stack.Count);
        
        stack.Push(3000);
        stack.Push(3500);
        stack.Push(4000);
        
        Console.WriteLine("\nStack elements...updated");
        foreach(int val in stack) {
            Console.WriteLine(val.ToString());
        }
        Console.WriteLine("\nCount of elements (updated) = " + stack.Count);
        
        Console.WriteLine("\nStack object toString(): " + stack.ToString());
    }
}

The output of the above code is −

Stack elements...
2500
2000
1500
1250
1000
750
500
300
150
Count of elements = 9

Stack elements...updated
4000
3500
3000
2500
2000
1500
1250
1000
750
500
300
150

Count of elements (updated) = 12

Stack object toString(): System.Collections.Stack

Using ToString() with String Elements

The following example shows using ToString() on string elements in a stack −

using System;
using System.Collections;

public class Demo {
    public static void Main() {
        Stack stack = new Stack();
        stack.Push("Inspiron");
        stack.Push("Alienware");
        stack.Push("Projectors");
        stack.Push("Monitors");
        stack.Push("XPS");
        stack.Push("Laptop");
        stack.Push("Notebook");
        
        Console.WriteLine("Stack elements...");
        foreach(string val in stack) {
            Console.WriteLine(val.ToString());
        }
        Console.WriteLine("Count of elements = " + stack.Count);
        Console.WriteLine("Element at the top = " + stack.Peek());
        
        stack.Push("Ultrabook");
        stack.Push("Cameras");
        stack.Push("Keyboards");
        
        Console.WriteLine("\nStack elements...updated");
        foreach(string val in stack) {
            Console.WriteLine(val.ToString());
        }
        Console.WriteLine("Element at the top = " + stack.Peek());
        Console.WriteLine("\nCount of elements (updated) = " + stack.Count);
        
        Console.WriteLine("Stack type: " + stack.ToString());
        
        stack.Clear();
        Console.WriteLine("Count of elements (after clear) = " + stack.Count);
    }
}

The output of the above code is −

Stack elements...
Notebook
Laptop
XPS
Monitors
Projectors
Alienware
Inspiron
Count of elements = 7
Element at the top = Notebook

Stack elements...updated
Keyboards
Cameras
Ultrabook
Notebook
Laptop
XPS
Monitors
Projectors
Alienware
Inspiron
Element at the top = Keyboards

Count of elements (updated) = 10
Stack type: System.Collections.Stack
Count of elements (after clear) = 0

Key Points

• The Stack.ToString() method returns the type name, not the stack contents.

• To display stack elements, iterate through the collection and call ToString() on individual items.

• Stack follows LIFO (Last In, First Out) principle − the most recently added element is at the top.

• Use Peek() to view the top element without removing it from the stack.

Conclusion

The Stack.ToString() method returns the type information of the stack object rather than its contents. To display actual stack elements, you must iterate through the collection and call ToString() on each individual element, which is useful for debugging and displaying stack contents.