Check if a list is empty in C#

This post will discuss how to determine whether a list is empty in C#. The solution should return true if the list contains any elements; otherwise, false.

1. Using `Enumerable.Any()` method (`System.Linq`)

To determine whether a list contains any elements, we can use the Enumerable.Any() method. The following example demonstrates this use of Any.

using System;

using System.Collections.Generic;

using System.Linq;

public class Example

{

public static bool IsEmpty<T>(List<T> list)

{

if (list == null) {

return true;

}

return !list.Any();

}

public static void Main()

{

List<int> list = new List<int>();

bool isEmpty = IsEmpty(list);

if (isEmpty) {

Console.WriteLine("List is Empty");

}

else {

Console.WriteLine("List contains elements");

}

Output: List is Empty

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2. Using `Enumerable.FirstOrDefault()` method (`System.Linq`)

The Enumerable.FirstOrDefault() method returns the first element of a sequence. If no elements are found, FirstOrDefault returns a default value. We can use this to check for an empty list as follows:

using System;

using System.Linq;

using System.Collections.Generic;

public class Example

{

public static bool IsEmpty<T>(List<T> list)

{

if (list == null) {

return true;

}

return list.FirstOrDefault() != null;

}

public static void Main()

{

List<int> list = new List<int>();

bool isEmpty = IsEmpty(list);

if (isEmpty) {

Console.WriteLine("List is Empty");

}

else {

Console.WriteLine("List contains elements");

}

Output: List is Empty

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3. Using `Enumerable.Count()` method (`System.Linq`)

Another approach is to use the Enumerable.Count() method, which returns the total number of elements in a sequence.

using System;

using System.Collections.Generic;

public class Example

{

public static bool IsEmpty<T>(List<T> list)

{

if (list == null) {

return true;

}

return list.Count == 0;

}

public static void Main()

{

List<int> list = new List<int>();

bool isEmpty = IsEmpty(list);

if (isEmpty) {

Console.WriteLine("List is Empty");

}

else {

Console.WriteLine("List contains elements");

}

Output: List is Empty

Download Run Code

That’s all about determining whether a list is empty in C#.

Check if a list is empty in C#

1. Using Enumerable.Any() method (System.Linq)

2. Using Enumerable.FirstOrDefault() method (System.Linq)

3. Using Enumerable.Count() method (System.Linq)

Share this:

1. Using `Enumerable.Any()` method (`System.Linq`)

2. Using `Enumerable.FirstOrDefault()` method (`System.Linq`)

3. Using `Enumerable.Count()` method (`System.Linq`)