How to Find Length of Array in C# - Simple Guide

In C#, you find the length of an array using the Length property. For example, array.Length returns the number of elements in the array.

Syntax

Use the Length property on an array variable to get the total number of elements it contains.

• array: Your array variable.
• Length: Property that returns the size of the array as an integer.

csharp

int length = array.Length;

Example

This example shows how to create an array and print its length using the Length property.

csharp

using System;

class Program
{
    static void Main()
    {
        int[] numbers = { 10, 20, 30, 40, 50 };
        Console.WriteLine("Length of array: " + numbers.Length);
    }
}

Output

Length of array: 5

Common Pitfalls

Some common mistakes when finding array length in C# include:

• Trying to use Count() method which is for collections, not arrays.
• Confusing Length with the last index (which is Length - 1).
• Using Length on a null array causes a NullReferenceException.

csharp

/* Wrong way: Using Count() on array */
// int count = array.Count(); // This causes error unless using LINQ

/* Right way: Use Length property */
int length = array.Length;

Quick Reference

Remember these quick tips when working with array length in C#:

• Use array.Length to get the number of elements.
• Array indices go from 0 to Length - 1.
• Length is a property, not a method (no parentheses).

Key Takeaways

Use the Length property to get the number of elements in a C# array.

Array indices start at 0, so the last index is Length minus one.

Length is a property, so do not use parentheses when accessing it.

Avoid using Count() on arrays unless you include LINQ and understand the difference.

Check for null arrays before accessing Length to prevent errors.