如何使用索引号制作对象

Question

我想让我的程序比现在更短。 我制作了 8 个不同的对象并用它们做事，但我想用 for 循环和索引号之类的东西来制作它。 有没有办法做到这一点，因为我已经查过了，但似乎没有找到任何东西。

物品之类的东西是荷兰语，对此感到抱歉。

private void AankomstButton_Click(object sender, EventArgs e)
    {
        if (welkKind == 1)
        {
            if (File.Exists(@"Bestanden/" + kind1.Naam + "_" + DateTime.Now.ToString("Y") + ".txt") == false)
            {
                using (StreamWriter sw = new StreamWriter(@"Bestanden/" + kind2.Naam + "_" + DateTime.Now.ToString("Y") + ".txt")) ;

            }
            else
            {
                using (StreamWriter sw = File.AppendText(@"Bestanden/" + kind2.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {

                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }                   

            }
        }


        if (welkKind == 2)
        {
            if (File.Exists(@"Bestanden/" + kind2.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
            {
                using (StreamWriter sw = File.AppendText(@"Bestanden/" + kind2.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
            else
            {
                using (StreamWriter sw = new StreamWriter(@"Bestanden/" + kind2.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
        }
        if (welkKind == 3)
        {
            if (File.Exists(@"Bestanden/" + kind3.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
            {
                using (StreamWriter sw = File.AppendText(@"Bestanden/" + kind3.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
            else
            {
                using (StreamWriter sw = new StreamWriter(@"Bestanden/" + kind3.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
        }
        if (welkKind == 4)
        {
            if (File.Exists(@"Bestanden/" + kind4.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
            {
                using (StreamWriter sw = File.AppendText(@"Bestanden/" + kind4.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
            else
            {
                using (StreamWriter sw = new StreamWriter(@"Bestanden/" + kind4.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
        }
        if (welkKind == 5)
        {
            if (File.Exists(@"Bestanden/" + kind5.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
            {
                using (StreamWriter sw = File.AppendText(@"Bestanden/" + kind5.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
            else
            {
                using (StreamWriter sw = new StreamWriter(@"Bestanden/" + kind5.Naam + "_" + DateTime.Now.ToString("Y") + ".txt"))
                {
                    sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
                }
            }
        }

Answer 1

如果您保留一个子数组 (kind)，则可以通过索引访问该数组。

Kind[] children = new Kind[] { kind1, kind2 };

if (welkKind >= 0 && welkKind < children.Length)
{
    Kind kind = children[welkKind];

    string fileName = @"Bestanden/" + kind.Naam + "_" + DateTime.Now.ToString("Y") + ".txt";
    if (File.Exists(fileName))
    {
        using (StreamWriter sw = new StreamWriter(fileName))
        {
            sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
        }
    }
    else
    {
        using (StreamWriter sw = File.AppendText(fileName))
        {
            sw.WriteLine(DateTime.Now.ToString("d") + " Aangekomen: " + DateTime.Now.ToString("t"));
        }
    }
}

另一个选项是列表，它的使用语法类似，但您可以动态添加和删除列表中的项目：

List<Kind> children = new List<Kind>();
children.Add(kind1);
children.Add(kind2);
children.Add(new Kind() { Naam = "John" });

if (welkKind >= 0 && welkKind < children.Count)
{
    Kind kind = children[welkKind];
}