Add implementation

ProcessCpuUsage.cs

@@ -0,0 +1,60 @@
+using System;
+using System.Diagnostics;
+
+namespace ProcessCpuUsageStatusWindow
+{
+    public class ProcessCpuUsage
+    {
+        #region Properties
+
+        public string ProcessName { get; private set; }
+        public float PercentUsage { get; internal set; }
+        public DateTime LastFound { get; set; }
+        public bool UsageValid { get; private set; }
+
+        internal CounterSample LastSample { get; set; }
+
+        #endregion
+
+        #region Constructor
+
+        internal ProcessCpuUsage(InstanceData instanceData)
+            : this(instanceData, DateTime.MinValue)
+        { }
+
+        internal ProcessCpuUsage(InstanceData instanceData, DateTime timestamp)
+        {
+            // Store the process details
+            ProcessName = instanceData.InstanceName;
+
+            // Store the initial data
+            LastFound = timestamp;
+            LastSample = instanceData.Sample;
+
+            // We start out as not valid
+            UsageValid = false;
+        }
+
+        #endregion
+
+        #region Usage update
+
+        internal void UpdateCpuUsage(InstanceData instanceData, DateTime timestamp)
+        {
+            // Get the new sample
+            var newSample = instanceData.Sample;
+
+            // Calculate percent usage
+            PercentUsage = CounterSample.Calculate(LastSample, newSample) / Environment.ProcessorCount;
+
+            // Update the last sample and timestmap
+            LastSample = newSample;
+            LastFound = timestamp;
+
+            // Usage is now valid
+            UsageValid = true;
+        }
+
+        #endregion
+    }
+}