The ```Array``` class in the ```System``` namespace provides the **```Clear()``` method**, which sets a range of array elements to their default value in C#.

# Syntax
```
public static void Clear (Array array, int index, int length);
```
- It takes the `Array` that needs to be cleared, the starting `index` of the range of elements, and the `number of elements` to clear as inputs to the function.

- It throws an exception if the input array is `null`, if the `index` is less than the lower bound of the array, or if the sum of `index` and `length` is greater than the array’s length.

# Things to note
- The `Clear()` method resets the elements to their default type value. All #key# reference types values :e.g., string, object, interface #key# are set to `null`. All value types are set to their known default value, such as Boolean to false, integers to #key# 0 :zero #key#, etc. 
It does not delete the element, but only resets the value to the type's default value.
- This is an O(n) operation.




# Code
In the code below, we have created an integer array and a Boolean array, then used the `Array`. The `Clear()` method sets the range of values passed as input to their default values. The array elements are printed before and after the ```Clear()``` operation.

>Notice that in the output below, the values are set to #key# 0 :zero #key# for integers, and set to `false` for the Boolean array for the specified range in the array.



using System;

class HelloWorld
{
    static void Main()
    {
        int[] integerArray = {12,34,34,44};
        Console.WriteLine("Integer Array Before Clear()");
        Console.WriteLine("{0}", string.Join(",",integerArray));
        Array.Clear(integerArray, 0,3);
        Console.WriteLine("Integer Array After Clear()");
        Console.WriteLine("{0}", string.Join(",",integerArray));

        bool[] boolArray = {true, true, true, true, true};
        Console.WriteLine("Boolean Array Before Clear()");
        Console.WriteLine("{0}", string.Join(",",boolArray));
        Array.Clear(boolArray, 2,2);
        Console.WriteLine("Boolean Array After Clear()");
        Console.WriteLine("{0}", string.Join(",",boolArray));
    }

}

How to set array elements to their default value in C#

The `Clear()` method in C# sets a specified range of array elements to their default type values, like 0 for integers or `false` for Booleans.