c#でTaskを返す<br>Tとの大まかな使い方


        ,               ,                 ,        ,          ,           。
             ,            :PreCheck(),Check(),AfterCheck()。                      ,        ,    Task。          :      ,          ,    return  。
             ,      :        protected virtual Task PreCheck()  ,   return Task.Factory.StartNew(()=> { return true; });    ;       protected virtual async Task Check() ,    return true;    ;         。
               :
         1、Main  :
             static async System.Threading.Tasks.Task Main(string[] args)
    {
        var test = new ExtendClass();
        await test.Main();
        Console.WriteLine("Main Program here");
        Console.ReadKey();
    }
            2、MyBaseClass 
            public class MyBaseClass
{
    public async Task Main()
    {
        if (!await PreCheck())
        {
            Console.WriteLine("PreCheck not pass");
            return;
        }
        else
        {
            Console.WriteLine("PreCheck pass");
        }
        if (!await Check())
        {
            Console.WriteLine("Check not pass");
            return;
        }
        else
        {
            Console.WriteLine("Check pass");
        }
        if (!await AfterCheck())
        {
            Console.WriteLine("AfterCheck not pass");
            return;
        }
        else
        {
            Console.WriteLine("AfterCheck pass");
        }
        Console.WriteLine("Well done");
    }

    protected virtual Task PreCheck()
    {
        Console.WriteLine("Base PreCheck");
        return Task.Factory.StartNew(()=> { return true; });
    }

    protected virtual async Task Check()
    {
        Console.WriteLine("Base Check");
        return true;
    }

    protected virtual Task AfterCheck()
    {
        Console.WriteLine("Base AfterCheck");
        return Task.Factory.StartNew(() => { return true; });
    }
}
    3、ExtendClass 
    class ExtendClass:MyBaseClass
{
    private bool someCondiction = true;
    protected override async Task PreCheck()
    {
        if (!await base.PreCheck())
            return false;
        return await AnotherPreCheck();
    }

    protected override async Task Check()
    {
        if(someCondiction)
        {
            Console.WriteLine("Extend Check");
            return true;
        }
        else
        {
            return await base.Check();
        }
    }

    protected override Task AfterCheck()
    {
        return base.AfterCheck();
    }

    private async Task AnotherPreCheck()
    {
        Console.WriteLine("Extend AnotherPrecheck");
        return true;
    }
}