Setting every element in an array to a given value

Given the length of an array and a char, I would like to replace every element in a char array with that given char.

Using a for loop, I'm changing each element to that char. Is there a better way to do it, or a specific method for that?

using System;
using System.Collections.Generic;

namespace TestProject
{
    class Solution
    {
        static void TestMethod()
        {
            //lines of code
            int lengthOfArray = int.Parse(Console.ReadKey());
            char charReplace = Console.ReadKey().KeyChar;

            char[] arrayChar = new char[lengthOfArray];
            for (int i = 0; i < lengthOfArray; i++)
            {
                arrayChar[i] = charReplace;
            }
        }
    }
}

You can also use the static Array.Fill to quickly initialize an array to a given value:

bool[] isPrime = new bool[500];
Array.Fill(isPrime, true);

This will set all items in the array to true.

As mentioned in the comments by Pieter Witvoet, this feature is available in .NET Core only.

StackExchange Code Review Q#79058, answer score: 7