<PackageReference Include="NETStandard.Library" Version="2.0.0-preview2-25401-01" />

System.Random

public class Random
namespace System { public class Random { public Random(); public Random(int Seed); public virtual int Next(); public virtual int Next(int maxValue); public virtual int Next(int minValue, int maxValue); public virtual void NextBytes(byte[] buffer); public virtual double NextDouble(); protected virtual double Sample(); } }