CsharpHow-ToBeginner · 3 min read

How to Create Array in C#: Syntax and Examples

In C#, you create an array using the type[] arrayName = new type[size]; syntax, where type is the data type and size is the number of elements. You can also initialize an array with values using type[] arrayName = {value1, value2, ...};.

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Syntax

To create an array in C#, use the following syntax:

type[] arrayName; declares an array variable.
new type[size]; creates the array with a fixed size.
You can also initialize the array with values directly.

csharp

int[] numbers = new int[5];
string[] names = { "Alice", "Bob", "Charlie" };

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Example

This example shows how to create an integer array, assign values, and print them.

csharp

using System;

class Program
{
    static void Main()
    {
        int[] numbers = new int[3];
        numbers[0] = 10;
        numbers[1] = 20;
        numbers[2] = 30;

        foreach (int number in numbers)
        {
            Console.WriteLine(number);
        }
    }
}

Output

10 20 30

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Common Pitfalls

Common mistakes when creating arrays in C# include:

Forgetting to specify the size when using new.
Trying to change the size of an array after creation (arrays have fixed size).
Accessing indexes outside the array bounds, which causes errors.

Always remember arrays start at index 0.

csharp

int[] arr = new int[3];
// Wrong: arr = new int[0]; // Missing size

// Wrong: arr[3] = 5; // Index out of range

// Right:
arr[0] = 1;
arr[1] = 2;
arr[2] = 3;

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Quick Reference

Summary of array creation in C#:

Syntax	Description
`type[] name = new type[size];`	Create array with fixed size
`type[] name = { val1, val2, ... };`	Create and initialize array
`name[index]`	Access element at index (0-based)

Syntax	Description
type[] name = new type[size];	Create array with fixed size
type[] name = { val1, val2, ... };	Create and initialize array
name[index]	Access element at index (0-based)

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Key Takeaways

Use type[] name = new type[size]; to create an array with a fixed size.

You can initialize arrays directly with values using type[] name = { val1, val2, ... };.

Array indexes start at 0 and go up to size minus one.

Arrays in C# have a fixed size and cannot be resized after creation.

Always avoid accessing indexes outside the array bounds to prevent errors.