using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
 
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            // 非同期で1文字読み取るタスク
            Func<ConsoleKeyInfo> readAsync = () => Console.ReadKey(true);
            var task = Task.Factory.StartNew(readAsync);
 
            while (true)
            {
                if (task.IsCompleted)
                {
                    Console.WriteLine(task.Result.KeyChar + "が押されました");
 
                    if (task.Result.KeyChar == 'D')
                    {
                        //ここでは文字列を得たい
                        string input = Console.ReadLine();
                        Console.WriteLine(input + "が入力されました");
 
                        if (input == "sss")
                        {
                            //sssが入力された時、処理を行う
                            break;
                        }
                    }
 
                    task = Task.Factory.StartNew(readAsync);
                }
            }
        }
    }
}
 

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