using System;

using System.Threading;

using System.Threading.Tasks;

​

public class Program

{

    public static void Main()

    {

        var task = RunTask()

            .ContinueWith(t => {

                Console.WriteLine($"task status is {t.Status}, IsCompleted: {t.IsCompleted}, IsCompletedSuccessfully: {t.IsCompletedSuccessfully}");

                if (t.IsCompletedSuccessfully){

                    var result = t.Result;

                    if (result.IsSuccess){

                        Console.WriteLine("task is ok!..");

                    }

                }

                if (t.Exception != null){

                    Console.WriteLine("Task is faulted: {0}", t.Exception.Message);

                }

                return new CallResult(false);

            });

        Task.WaitAll(new []{task});

        var result = task.Result;

        Console.WriteLine(result);

    }

​

    public static async Task<CallResult> RunTask() {

        Console.WriteLine("task is running!..");

        throw new Exception("force to error");

        return new CallResult(true);

    }

​

}

​

public class CallResult {

​

    public  CallResult(bool isSuccess) {

            IsSuccess = isSuccess;

    }

    public bool IsSuccess {get; set;}

    public override string ToString(){

            return $"CallResult is {IsSuccess}";

    }

}

​

​