Using task await and Task.FromResult properly - any issues predicted

[cally_kalpana]

Hi all

I created this code with the help of asking question in forum. The main purpose of the code is to read values from 6 functions at the same times. I am using an external library functions as the code actually talks to the data acquisition software.

using IMLtools;
using System;
using System.Collections.Generic;
using System.Globalization;
using System.Threading.Tasks;
using System.Timers;
using System.Configuration;





namespace ConsoleApp12
{
class Program
{
static Logger testlogger = new Logger();
static IMLtoolsv6 newsd = new IMLtoolsv6();
static int tableWidth = 180;
static Timer aTimer;



static string channel1 = ConfigurationManager.AppSettings["channel1name"];
static string channel2 = ConfigurationManager.AppSettings["channel2name"];
static string channel3 = ConfigurationManager.AppSettings["channel3name"];
static string channel4 = ConfigurationManager.AppSettings["channel4name"];
static string channel5 = ConfigurationManager.AppSettings["channel5name"];
static string channel6 = ConfigurationManager.AppSettings["channel6name"];

static void Main(string[] args)
{


string IMSfilespec = "C:\\Windmill\\setups\\NEWCONFI.IMS";
string IMSname = "NEWCONFI.IMS";

try
{
newsd.IMLOpen();
newsd.IMSLoadFile(IMSfilespec, IMSname);
testlogger.Log("Successful connection to IMS");
}
catch(Exception ex)
{
testlogger.Log(ex.ToString());
}


PrintLine();
PrintRow("Time","Channel 1","Channel 2", "Channel 3", "Channel 4", "Channel 5","Channel 6");
PrintLine();
SetTimer();


}



private static void PrintLine()
{
Console.WriteLine(new string('-', tableWidth));
}

static void PrintRow(params string[] columns)
{
int width = (tableWidth - columns.Length) / columns.Length;
string row = "|";

foreach (string column in columns)
{
row += AlignCentre(column, width) + "|";

}

Console.WriteLine(row);
}

static string AlignCentre(string text, int width)
{
text = text.Length > width ? text.Substring(0, width - 3) + "..." : text;

if (string.IsNullOrEmpty(text))
{
return new string(' ', width);
}
else
{
return text.PadRight(width - (width - text.Length) / 2).PadLeft(width);
}
}

private static void SetTimer()
{
try
{
aTimer = new Timer();
aTimer.Elapsed += OnTimedEvent;
aTimer.Interval = 1000;
aTimer.Enabled = true;
Console.ReadKey();
}
// Create a timer with a two second interval.
catch (Exception ex)
{
testlogger.Log(ex.ToString());
}
}

public static async void OnTimedEvent(Object source, ElapsedEventArgs e)
{

//Task<string> task1 = Task.Run(() => readChannel1());
//task1.Wait();
//Task<string> task2 = Task.Run(() => readChannel2());
//task2.Wait();
//Task<string> task3 = Task.Run(() => readChannel3());
//task3.Wait();
//Task<string> task4 = Task.Run(() => readChannel4());
//task4.Wait();
//Task<string> task5 = Task.Run(() => readChannel5());
//task5.Wait();
//Task<string> task6 = Task.Run(() => readChannel6());
//task6.Wait();
try
{
Task<string> task1 = readChannel1();
task1.Wait();
Task<string> task2 = readChannel2();
task2.Wait();
Task<string> task3 = readChannel3();
task3.Wait();
Task<string> task4 = readChannel4();
task4.Wait();
Task<string> task5 = readChannel5();
task5.Wait();
Task<string> task6 = readChannel6();
task6.Wait();



List<Task<string>> tasklist = new List<Task<string>>();
tasklist.Add(task1);
tasklist.Add(task2);
tasklist.Add(task3);
tasklist.Add(task4);
tasklist.Add(task5);
tasklist.Add(task6);

string[] storearray = await Task.WhenAll(tasklist);

PrintRow(DateTime.Now.ToString(), storearray[0], storearray[1], storearray[2], storearray[3], storearray[4], storearray[5]);
testlogger.extractitout(DateTime.Now + "," + string.Join(", ", storearray));
}
catch(Exception ex)
{
testlogger.Log(ex.ToString());
}

}

public static async Task<string> readChannel1()
{

string result1 = " ";
//string s = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss fff", CultureInfo.InvariantCulture);
newsd.ReadFromChannel(channel1, result1);
//result1 = newsd.IML_LastDataString;
result1 = await Task.FromResult(newsd.IML_LastDataString);
return "Result 1 " + result1;


}

public static async Task<string> readChannel2()
{

string result2 = " ";
//string s = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss fff", CultureInfo.InvariantCulture);
newsd.ReadFromChannel(channel2, result2);
result2 = await Task.FromResult(newsd.IML_LastDataString);
return "Result 2 " + result2;


}

public static async Task<string> readChannel3()
{

string result3 = " ";
//string s = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss fff", CultureInfo.InvariantCulture);
newsd.ReadFromChannel(channel3, result3);
result3 = await Task.FromResult(newsd.IML_LastDataString);

return "Result 3 " + result3;


}

public static async Task<string> readChannel4()
{

string result4 = " ";
//string s = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss fff", CultureInfo.InvariantCulture);
newsd.ReadFromChannel(channel4, result4);
result4 = await Task.FromResult(newsd.IML_LastDataString);

return "Result 4 " + result4;

}

public static async Task<string> readChannel5()
{
string result5 = " ";
//string s = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss fff", CultureInfo.InvariantCulture);
newsd.ReadFromChannel(channel5, result5);
result5 = await Task.FromResult(newsd.IML_LastDataString);

return "Result 5 " + result5;
}

public static async Task<string> readChannel6()
{
string result6 = " ";
//string s = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss fff", CultureInfo.InvariantCulture);
newsd.ReadFromChannel(channel6, result6);
result6 = await Task.FromResult(newsd.IML_LastDataString);

return "Result 6 " + result6;
}


}
}



I was not using the Task.FromResult earlier, however I checked through the net and I am able to use it. The thing is I need all the readChannel functions to read the value at the same time. It is working now, but I would like to know what issues can I expect and how can I further improve it. I was reading and found some stuff on cache issues. Am I using the methods properly ?

Earlier without the Task.FromResult, the values returned from the

(newsd.IML_LastDataString)

was jumping from one channel to another.


Please advice.

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