C # Calculates the run time of a piece of code

The first method takes advantage of System.DateTime.Now:static void subtest () {DateTime Befordt = System.DateTime.Now;　　Time-consuming code DateTime Afterdt = System.DateTime.Now;　　TimeSpan ts = afterdt.subtract (Befordt); Console.WriteLine ("DateTime total Cost {0}ms.", TS.) TotalMilliseconds);}　　The second type is used with the Stopwatch class (system.diagnostics): static void Subtest () {Stopwatch SW = new Stopwatch (); Sw. 　　Start (); Time-consuming great code SW.　　Stop (); TimeSpan TS2 = sw.　　Elapsed; Console.WriteLine ("Stopwatch total cost {0}ms.", Ts2. TotalMilliseconds);} The third is implemented with the API: [System.Runtime.InteropServices.DllImport ("Kernel32.dll")]static extern bool QueryPerformanceCounter ( Ref long Count); [System.Runtime.InteropServices.DllImport ("Kernel32.dll")]static extern bool QueryPerformanceFrequency (ref long　　count); static void Subtest () {Long count = 0;　　Long count1 = 0;　　Long freq = 0;　　Double result = 0;　　QueryPerformanceFrequency (ref freq); 　　QueryPerformanceCounter (ref count);　　Time-consuming Code QueryPerformanceCounter (ref count1);　　Count = Count1-count; result = (double) (count)/(double) Freq; Console.WriteLine ("QueryPerformanceCounter time: {0} seconds", result);} You can also use a delegate to encapsulate it for easy invocation:///<summary>/////</summary>//<param name= "function" > code to be executed &LT;/PA ram>//<returns> Execute this piece of code time, in milliseconds </returns> public static string Stopwatch (Action function) {S Ystem.       diagnostics.stopwatch SW = new System.Diagnostics.Stopwatch (); Sw.        Start ();        Start execution of business code function (); Sw.       Stop (); TimeSpan timespan = SW.        Elapsed;   Return (Timespan.totalmilliseconds) + "MS"; }

　　

C # Calculates the run time of a piece of code