System.Diagnostics.PerformanceCounter.NextSample C# (CSharp) Method

        public System.Diagnostics.CounterSample NextSample() { throw null; }
        public float NextValue() { throw null; }

        public void WatchCpuAndMemory()
        {
            var pc = new PerformanceCounter("Processor Information", "% Processor Time");
            var cat = new PerformanceCounterCategory("Processor Information");
            var cpuInstances = cat.GetInstanceNames();
            var cpus = new Dictionary<string, CounterSample>();

            var memoryCounter = new PerformanceCounter("Memory", "Available MBytes");

            foreach (var s in cpuInstances)
            {
                pc.InstanceName = s;
                cpus.Add(s, pc.NextSample());
            }
            var t = DateTime.Now;
            while (t.AddMinutes(1) > DateTime.Now)
            {
                Trace.WriteLine(string.Format("Memory:{0}MB", memoryCounter.NextValue()));

                foreach (var s in cpuInstances)
                {
                    pc.InstanceName = s;
                    Trace.WriteLine(string.Format("CPU:{0} - {1:f}", s, Calculate(cpus[s], pc.NextSample())));
                    cpus[s] = pc.NextSample();
                }

                //Trace.Flush();
                System.Threading.Thread.Sleep(1000);
            }
        }