Question

我最近在@edplunkett看到了这段代码，并认为这对我正在做的事情有用，但是我想修改为包含缩进：

static void Main()
{
var randomCrap = new List<Object>
{
    1, "two",
    new List<object> { 3, 4 },
    5, 6,
    new List<object> {
        new List<object> { 7, 8, "nine" },
    },
};

randomCrap.PrintAll();
}

public static class Extensions
{
    public static void PrintAll(this Object root)
    {
        foreach (var x in root.SelectAll())
        {
            Console.WriteLine(x);
        }
    }

    public static IEnumerable<Object> SelectAll(this object o)
    {
        //  Thank you, eocron
        if (o is String)
        {
            yield return o;
        }
        else if (o is IEnumerable)
        {
            var e = o as IEnumerable;
            foreach (var child in e)
            {
                foreach (var child2 in child.SelectAll())
                    yield return child2;
            }
        }
        else
        {
            yield return o;
        }
    }
}

每次遇到IEnumerable时添加缩进是多么容易，这样你就可以得到：

1
two
  3
  4
5
6
  7
  8
  nine

类似于0的起始缩进，每遇到IEnumerable会增加一个？

Answer 1

那将是一个很大的变化。现在，它传递给Function，并从中返回单个对象。你必须改变它来传递和返回两件事：eobject和缩进级别。它可以做到，但会破坏@ edplunkett设计的优雅。

更新：实际上，对于Tuples来说，它毕竟不是那么糟糕::

static void Main()
{
    var randomCrap = new List<Object>
{
    1, "two",
    new List<object> { 3, 4 },
    5, 6,
    new List<object> {
        new List<object> { 7, 8, "nine" },
    },
};

    randomCrap.PrintAll();
}

public static class Extensions
{
    public static void PrintAll(this Object root)
    {
        foreach (var x in root.SelectAll(0))
        {
            Console.WriteLine("{0}{1}", new string('_', x.indent),x.obj);
        }
    }

    public static IEnumerable<(Object obj,int indent)> 
                     SelectAll(this object o, int indent)
    {
        //  Thank you, eocron
        if (o is String)
        {
            yield return (o,indent);
        }
        else if (o is IEnumerable)
        {
            var e = o as IEnumerable;
            foreach (var child in e)
            {
                foreach (var child2 in child.SelectAll(indent+1))
                    yield return child2;
            }
        }
        else
        {
            yield return (o, indent);
        }
    }
}

Answer 2

您可以使用元组轻松完成：

public static class Extensions
{
    public static void PrintAll(this Object root)
    {
        foreach (var x in root.SelectAll(""))
        {
            Console.WriteLine(x.Item1 + x.Item2);
        }
    }

    public static IEnumerable<(string, Object)> SelectAll(this object o, string indentation)
    {
        //  Thank you, eocron
        if (o is String)
        {
            yield return (indentation, o);
        }
        else if (o is IEnumerable)
        {
            var e = o as IEnumerable;
            foreach (var child in e)
            {
                foreach (var child2 in child.SelectAll(indentation + "  "))
                    yield return (child2.Item1, child2.Item2);
            }
        }
        else
        {
            yield return (indentation, o);
        }
    }
}

编辑：这是一个前C＃7版本（未经测试，但应该有效）：

public static class Extensions
{
    public static void PrintAll(this Object root)
    {
        foreach (var x in root.SelectAll(""))
        {
            Console.WriteLine(x.Item1 + x.Item2);
        }
    }

    public static IEnumerable<Tuple<string, Object>> SelectAll(this object o, string indentation)
    {
        //  Thank you, eocron
        if (o is String)
        {
            yield return Tuple.Create(indentation, o);
        }
        else if (o is IEnumerable)
        {
            var e = o as IEnumerable;
            foreach (var child in e)
            {
                foreach (var child2 in child.SelectAll(indentation + "  "))
                    yield return Tuple.Create(child2.Item1, child2.Item2);
            }
        }
        else
        {
            yield return Tuple.Create(indentation, o);
        }
    }
}

我需要做些什么来修改它以包含缩进？

2 个答案: