methode random c# code example
Example 1: c# random
using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
public class Example
{
static Object randLock, numericLock;
static Random rand;
static CancellationTokenSource source;
double totalValue = 0.0;
int totalCount = 0;
public Example()
{
rand = new Random();
randLock = new Object();
numericLock = new Object();
source = new CancellationTokenSource();
}
public static async Task Main()
{
Example ex = new Example();
Thread.CurrentThread.Name = "Main";
await ex.Execute();
}
private Task Execute()
{
List<Task> tasks = new List<Task>();
for (int ctr = 0; ctr <= 10; ctr++)
{
CancellationToken token = source.Token;
int taskNo = ctr;
tasks.Add(Task.Run( () =>
{
double previous = 0.0;
int taskCtr = 0;
double taskTotal = 0.0;
double result = 0.0;
for (int n = 0; n < 2000000; n++)
{
// Make sure there's no corruption of Random.
token.ThrowIfCancellationRequested();
lock (randLock) {
result = rand.NextDouble();
}
// Check for corruption of Random instance.
if ((result == previous) && result == 0) {
source.Cancel();
}
else {
previous = result;
}
taskCtr++;
taskTotal += result;
}
// Show result.
Console.WriteLine("Task {0} finished execution.", taskNo);
Console.WriteLine("Random numbers generated: {0:N0}", taskCtr);
Console.WriteLine("Sum of random numbers: {0:N2}", taskTotal);
Console.WriteLine("Random number mean: {0:N4}\n", taskTotal/taskCtr);
// Update overall totals.
lock (numericLock) {
totalCount += taskCtr;
totalValue += taskTotal;
}
},
token));
}
try {
await Task.WhenAll(tasks.ToArray());
Console.WriteLine("\nTotal random numbers generated: {0:N0}", totalCount);
Console.WriteLine("Total sum of all random numbers: {0:N2}", totalValue);
Console.WriteLine("Random number mean: {0:N4}", totalValue/totalCount);
}
catch (AggregateException e) {
foreach (Exception inner in e.InnerExceptions) {
TaskCanceledException canc = inner as TaskCanceledException;
if (canc != null)
Console.WriteLine("Task #{0} cancelled.", canc.Task.Id);
else
Console.WriteLine("Exception: {0}", inner.GetType().Name);
}
}
finally {
source.Dispose();
}
}
}
// The example displays output like the following:
// Task 1 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 1,000,502.47
// Random number mean: 0.5003
//
// Task 0 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 1,000,445.63
// Random number mean: 0.5002
//
// Task 2 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 1,000,556.04
// Random number mean: 0.5003
//
// Task 3 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 1,000,178.87
// Random number mean: 0.5001
//
// Task 4 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 999,819.17
// Random number mean: 0.4999
//
// Task 5 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 1,000,190.58
// Random number mean: 0.5001
//
// Task 6 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 999,720.21
// Random number mean: 0.4999
//
// Task 7 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 999,000.96
// Random number mean: 0.4995
//
// Task 8 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 999,499.33
// Random number mean: 0.4997
//
// Task 9 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 1,000,193.25
// Random number mean: 0.5001
//
// Task 10 finished execution.
// Random numbers generated: 2,000,000
// Sum of random numbers: 999,960.82
// Random number mean: 0.5000
//
//
// Total random numbers generated: 22,000,000
// Total sum of all random numbers: 11,000,067.33
// Random number mean: 0.5000Example 2: c# random
// Instantiate random number generator using system-supplied value as seed.
var rand = new Random();
// Generate and display 5 random byte (integer) values.
var bytes = new byte[5];
rand.NextBytes(bytes);
Console.WriteLine("Five random byte values:");
foreach (byte byteValue in bytes)
Console.Write("{0, 5}", byteValue);
Console.WriteLine();
// Generate and display 5 random integers.
Console.WriteLine("Five random integer values:");
for (int ctr = 0; ctr <= 4; ctr++)
Console.Write("{0,15:N0}", rand.Next());
Console.WriteLine();
// Generate and display 5 random integers between 0 and 100.
Console.WriteLine("Five random integers between 0 and 100:");
for (int ctr = 0; ctr <= 4; ctr++)
Console.Write("{0,8:N0}", rand.Next(101));
Console.WriteLine();
// Generate and display 5 random integers from 50 to 100.
Console.WriteLine("Five random integers between 50 and 100:");
for (int ctr = 0; ctr <= 4; ctr++)
Console.Write("{0,8:N0}", rand.Next(50, 101));
Console.WriteLine();
// Generate and display 5 random floating point values from 0 to 1.
Console.WriteLine("Five Doubles.");
for (int ctr = 0; ctr <= 4; ctr++)
Console.Write("{0,8:N3}", rand.NextDouble());
Console.WriteLine();
// Generate and display 5 random floating point values from 0 to 5.
Console.WriteLine("Five Doubles between 0 and 5.");
for (int ctr = 0; ctr <= 4; ctr++)
Console.Write("{0,8:N3}", rand.NextDouble() * 5);
// The example displays output like the following:
// Five random byte values:
// 194 185 239 54 116
// Five random integer values:
// 507,353,531 1,509,532,693 2,125,074,958 1,409,512,757 652,767,128
// Five random integers between 0 and 100:
// 16 78 94 79 52
// Five random integers between 50 and 100:
// 56 66 96 60 65
// Five Doubles.
// 0.943 0.108 0.744 0.563 0.415
// Five Doubles between 0 and 5.
// 2.934 3.130 0.292 1.432 4.369