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How to make an efficient Console Updater

Currently i wanna display the following variable
Total Item
Total Execution
Finish Status
using System;
namespace ConsoleTest
{
class Program
{
static void Main(string[] args)
{
int TotalValue = 250; // Total Item Example
int TotalExecution = 0;
bool Finish_Status = false;
for (int i = 0; i < TotalValue; ++i)
{
//Do Work Here
System.Threading.Thread.Sleep(10); // Example Work
TotalExecution++;
if (TotalValue - TotalExecution == 0)
{
Finish_Status = true;
}
Console.Clear();
Console.Write("Progression Info\n Total Item : {0}\n Execution Total : {1}\n Remaining : {2}\n Finish_Status : {3}", TotalValue,TotalExecution, TotalValue - TotalExecution, Finish_Status); // Display Information To Console
}
Console.ReadLine();
}
}
}
The result is good,however i was wondering if theres a much more efficient way of doing this,preferably updating it without using Console.Clear();

You can use Console.SetCursorPosition to move the cursor around the console buffer for each write, rather than clearing the console each time.
For example:
using System;
namespace ConsoleTest
{
class Program
{
static void Main(string[] args)
{
int TotalValue = 250; // Total Item Example
int TotalExecution = 0;
bool Finish_Status = false;
Console.Write("Progression Info\n Total Item : \n Execution Total : \n Remaining : \n Finish_Status : ");
for (int i = 0; i < TotalValue; ++i)
{
//Do Work Here
System.Threading.Thread.Sleep(10); // Example Work
TotalExecution++;
if (TotalValue - TotalExecution == 0)
{
Finish_Status = true;
}
Console.SetCursorPosition(26, 1);
Console.Write(TotalValue);
Console.SetCursorPosition(31, 2);
Console.Write(TotalExecution);
Console.SetCursorPosition(25, 3);
Console.Write(TotalValue - TotalExecution);
Console.SetCursorPosition(29, 4);
Console.Write(Finish_Status);
}
Console.ReadLine();
}
}
}
Disclaimer: Obviously the above is quick 'n' dirty, and would benefit from substantial refinement, but you get the idea.

Welcome kepanin_lee
I think you are looking for something like this.
//Console.Clear()
Console.Write(vbCr & "Progression Info\n...
Just start with vbCr, by this way you force to start on the beginning of the same line, so you only overwrite the last line, without clear all the screen.

Multithreads - passing arguments and receiving results

I am trying various options on working with threads. I wrote the code below, but it does not work as expected. How can I fix the code, so that the main function will correctly display the product?
using System;
using System.Threading;
namespace MultiThreads
{
class Program
{
static int prod;
public static void Main(string[] args)
{
Thread thread = new Thread(() => Multiply(2, 3));
thread.Start();
for(int i = 0; i < 10; i++) { // do some other work until thread completes
Console.Write(i + " ");
Thread.Sleep(100);
}
Console.WriteLine();
Console.WriteLine("Prod = " + prod); // I expect 6 and it shows 0
Console.ReadKey(true);
}
public static void Multiply(int a, int b)
{
Thread.Sleep(2000);
prod = a * b;
}
}
}

Ignoring the fact that you should be using non-blocking tasks, volatile properties and other coroutine principals, the immediate reason your program does not work as intended is because you didn't re-join the child thread back into the parent. See Join
Without the join, the Console.WriteLine("Prod = " + prod); occurs before the assignment prod = a * b;
static int prod;
static void Main(string[] args)
{
Thread thread = new Thread(() => Multiply(2, 3));
thread.Start();
for (int i = 0; i < 10; i++)
{ // do some other work until thread completes
Console.Write(i + " ");
Thread.Sleep(100);
}
thread.Join(); // Halt current thread until the other one finishes.
Console.WriteLine();
Console.WriteLine("Prod = " + prod); // I expect 6 and it shows 0
Console.ReadKey(true);
}
public static void Multiply(int a, int b)
{
Thread.Sleep(2000);
prod = a * b;
}

Stopwatch and ReadKey don't work properly

I'm working on my multi-threading password cracker, only numbers. It must show how much time has passed to find the password. I used Stopwatch to find it, but in functions Stopwatch doesn't work. Here is my code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;
using System.Threading;
namespace ConsoleApplication4
{
class Program
{
static void Main(string[] args)
{
int psw = 14995399;
Stopwatch time = new Stopwatch();
Thread Thread1 = new Thread(islem1);
Thread Thread2 = new Thread(islem2);
Thread Thread3 = new Thread(islem3);
Thread Thread4 = new Thread(islem4);
time.Start();
Thread1.Start();
Thread2.Start();
Thread3.Start();
Thread4.Start();
Thread.Sleep(1000);
time.Stop();
System.Console.WriteLine("Time elapsed: {0}", time.Elapsed);
Console.ReadKey();
}
static void islem1()
{
for (int i = 00000000; i < 25000000; i++)
{
int psw = 14995399;
if (i == psw)
{
System.Console.WriteLine("Şifre=" + i);
time.Stop();
Console.WriteLine("Time elapsed: {0}", time.Elapsed);
Console.ReadKey();
}
}
}
static void islem2()
{
for (int i = 25000000; i < 50000000; i++)
{
int psw = 14995399;
if (i == psw)
{
System.Console.WriteLine("Şifre=" + i);
time.Stop();
Console.WriteLine("Time elapsed: {0}", time.Elapsed);
Console.ReadKey();
}
}
}
static void islem3()
{
for (int i = 50000000; i < 75000000; i++)
{
int psw = 14995399;
if (i == psw)
{
System.Console.WriteLine("Şifre=" + i);
time.Stop();
Console.WriteLine("Time elapsed: {0}", time.Elapsed);
Console.ReadKey();
}
}
}
static void islem4()
{
for (int i = 75000000; i < 100000000; i++)
{
int psw = 14995399;
if (i == psw)
{
System.Console.WriteLine("Şifre=" + i);
time.Stop();
Console.WriteLine("Time elapsed: {0}", time.Elapsed);
Console.ReadKey();
}
}
}
}
}

It's because your variable
Stopwatch time = new Stopwatch();
declared outside the visibility functions. The scope of visibility the var is your function Main. You can pass Stopwatch as a parameter to your functions:
Thread1.Start(time);
Or declare it as a class field:
class Program
{
private static Stopwatch time = new Stopwatch();
...
}
Note that you have just one Stopwatch instance then if you stop it in one thread it'll stopped in all application and elapsed time will not changed after that.
Then you should delete time.Stop(); from your Main method because it can caused the result in cased when your threads works longet then 1 second.
Also it's no reason to call Thread.Sleep(). Just delete this lines and your code continues work as expected.
Finally you can delete Console.ReadKey() from your thread functions because your main-thread already waits for user input.
The whole solution with configurable threads count can illustrate interesting results for different number of threads. Try the code below which can illustrate work with thread parameters and reduce lines of code:
using System;
using System.Diagnostics;
using System.Threading;
namespace ConsoleApplication4
{
internal class Program
{
private class BruteforceParams
{
public int StartNumber { get; set; }
public int EndNumber { get; set; }
}
private const int password = 14995399;
private static readonly Stopwatch time = new Stopwatch();
private static void Main(string[] args)
{
const int maxPassword = 100000000;
Console.WriteLine("Enter number of threads: ");
var threadsCountString = Console.ReadLine();
var threadsCount = int.Parse(threadsCountString);
var threads = new Thread[threadsCount];
for (int i = 0; i < threadsCount; i++)
{
var thread = new Thread(Bruteforce);
threads[i] = thread;
}
time.Start();
for (int i = 0; i < threadsCount; i++)
{
threads[i].Start(new BruteforceParams { StartNumber = i * maxPassword / threadsCount, EndNumber = (i + 1) * maxPassword / threadsCount });
}
Console.ReadKey();
}
private static void Bruteforce(object param)
{
var bp = (BruteforceParams) param;
for (int i = bp.StartNumber; i < bp.EndNumber; i++)
{
if (i == password)
{
Console.WriteLine("Şifre=" + i);
time.Stop();
Console.WriteLine("Time elapsed: {0}", time.Elapsed);
}
}
}
}
}

How do you think time.Stop(); going to work inside your function body islem1() or any other since you have defined the stopwatch inside Main() function body. You are bound to get compilation error saying time doesn't exist in current context.
static void islem1()
{
.............
time.Stop(); // this line of code
Console.WriteLine("Time elapsed: {0}", time.Elapsed);
Console.ReadKey();
}
}
}
Rather, you can create a separate watch per method and report that
static void islem1()
{
StopWatch time = Stopwatch.StartNew();
time.Stop(); // this line of code
Console.WriteLine("Time elapsed: {0}", time.Elapsed);
Console.ReadKey();
}

It's going to be difficult to extract meaningful timings using a single Stopwatch instance.
You might chose to make your timing measurements using a different pattern that uses a new Stopwatch for each measurement.
void Main()
{
var t1 = new Thread(_ => {
var sw = Stopwatch.StartNew();
DoSomething();
Console.WriteLine("took {0}ms", sw.ElapsedMilliseconds);
});
var t2 = new Thread(_ => {
var sw = Stopwatch.StartNew();
DoSomethingElse();
Console.WriteLine("took {0}ms", sw.ElapsedMilliseconds);
});
t1.Start();
t2.Start();
t1.Join();
t2.Join();
Console.ReadKey();
}
void DoSomething()
{
//do something
}
void DoSomethingElse()
{
//do something
}

How to block new threads until all threads are created and started

I am building a small application simulating a horse race in order to gain some basic skill in working with threads.
My code contains this loop:
for (int i = 0; i < numberOfHorses; i++)
{
horsesThreads[i] = new Thread(horsesTypes[i].Race);
horsesThreads[i].Start(100);
}
In order to keep the race 'fair', I've been looking for a way to make all newly created threads wait until the rest of the new threads are set, and only then launch all of them to start running their methods (Please note that I understand that technically the threads can't be launched at the 'same time')
So basically, I am looking for something like this:
for (int i = 0; i < numberOfHorses; i++)
{
horsesThreads[i] = new Thread(horsesTypes[i].Race);
}
Monitor.LaunchThreads(horsesThreads);

Threading does not promise fairness or deterministic results, so it's not a good way to simulate a race.
Having said that, there are some sync objects that might do what you ask. I think the Barrier class (Fx 4+) is what you want.

The Barrier class is designed to support this.
Here's an example:
using System;
using System.Threading;
namespace Demo
{
class Program
{
private void run()
{
int numberOfHorses = 12;
// Use a barrier with a participant count that is one more than the
// the number of threads. The extra one is for the main thread,
// which is used to signal the start of the race.
using (Barrier barrier = new Barrier(numberOfHorses + 1))
{
var horsesThreads = new Thread[numberOfHorses];
for (int i = 0; i < numberOfHorses; i++)
{
int horseNumber = i;
horsesThreads[i] = new Thread(() => runRace(horseNumber, barrier));
horsesThreads[i].Start();
}
Console.WriteLine("Press <RETURN> to start the race!");
Console.ReadLine();
// Signals the start of the race. None of the threads that called
// SignalAndWait() will return from the call until *all* the
// participants have signalled the barrier.
barrier.SignalAndWait();
Console.WriteLine("Race started!");
Console.ReadLine();
}
}
private static void runRace(int horseNumber, Barrier barrier)
{
Console.WriteLine("Horse " + horseNumber + " is waiting to start.");
barrier.SignalAndWait();
Console.WriteLine("Horse " + horseNumber + " has started.");
}
private static void Main()
{
new Program().run();
}
}
}
[EDIT] I just noticed that Henk already mentioned Barrier, but I'll leave this answer here because it has some sample code.

I'd be looking at a ManualResetEvent as a gate; inside the Thread, decrement a counter; if it is still non-zero, wait on the gate; otherwise, open the gate. Basically:
using System;
using System.Threading;
class Program
{
static void Main()
{
ManualResetEvent gate = new ManualResetEvent(false);
int numberOfThreads = 10, pending = numberOfThreads;
Thread[] threads = new Thread[numberOfThreads];
ParameterizedThreadStart work = name =>
{
Console.WriteLine("{0} approaches the tape", name);
if (Interlocked.Decrement(ref pending) == 0)
{
Console.WriteLine("And they're off!");
gate.Set();
}
else gate.WaitOne();
Race();
Console.WriteLine("{0} crosses the line", name);
};
for (int i = 0; i < numberOfThreads; i++)
{
threads[i] = new Thread(work);
threads[i].Start(i);
}
for (int i = 0; i < numberOfThreads; i++)
{
threads[i].Join();
}
Console.WriteLine("all done");
}
static readonly Random rand = new Random();
static void Race()
{
int time;
lock (rand)
{
time = rand.Next(500,1000);
}
Thread.Sleep(time);
}
}

showing percentage in .net console application

I have a console app that performs a lengthy process.
I am printing out the percent complete on a new line, for every 1% complete.
How can I make the program print out the percent complete in the same location in the console window?

Print \r to get back to the start of the line (but don't print a newline!)
For example:
using System;
using System.Threading;
class Test
{
static void Main()
{
for (int i=0; i <= 100; i++)
{
Console.Write("\r{0}%", i);
Thread.Sleep(50);
}
}
}

You may use:
Console.SetCursorPosition();
To set the position appropriately.
Like so:
Console.Write("Hello : ");
for(int k = 0; k <= 100; k++){
Console.SetCursorPosition(8, 0);
Console.Write("{0}%", k);
System.Threading.Thread.Sleep(50);
}
Console.Read();