C# 値渡し

using System;

namespace Chap3
{
class RPGClass
{
public void TestFunc(ref int a)
{
a *= 3;
Console.WriteLine(a);
}
}

class MainClass
{
    static void Main(string[] args)
    {
        RPGClass test = new RPGClass();
        int a = 5;

        test.TestFunc(ref a);
        Console.WriteLine(a);
    }
}

}