c# - 您如何将与集合中其他项目具有依赖性的项目分组？

Question

我需要找到一个漂亮、干净的方法来获得 IDictionary<string, ICollection<string>>字段及其相关依赖项。确定的方法是遍历一堆集合，寻找该集合中的那个字段，然后找到它所有不同的依赖项。示例代码:

public interface IFoo
{
    ICollection<string> Dependencies { get; }
}

public abstract class Foo<T> : IFoo
{
    protected Foo(ICollection<string> dependencies)
    {
        Dependencies = dependencies;
    }

    public ICollection<string> Dependencies { get; private set; }
}

public class FooA1 : Foo<A>
{
    public FooA1()
        :base(new Collection<string>() { "Amount", "CustomerDate", "AppointmentDate" }) { }
 }

public class FooA2 : Foo<A>
{
    public FooA2()
        :base(new Collection<string>() { "Amount", "AppointmentDate", "SomethingElse" }) { }
 }

public class FooA3 : Foo<A>
{
    public FooA3()
        :base(new Collection<string>() { "SomethingElse", "Something" }) { }
}

---

本质上，我想要实现的目标是这样的:

Amount => CustomerDate, AppointmentDate, SomethingElse
CustomerDate => Amount, AppointmentDate
AppointmentDate => Amount, CustomerDate, SomethingElse
SomethingElse => Amount, AppointmentDate, Something
Something => SomethingElse

现在，我知道如何获取所有字段的列表(假设我已经有了所有实例的列表):instances.SelectMany(i => i.Dependencies).Distinct();

问题是，如何以简洁的方式(最好使用 LINQ)获取该字段的所有依赖项列表。

Answer 1

这会输出您所要求的内容。这是我想到的第一件事，可能在某处可以对其进行优化。

var nice = instances.SelectMany(instance => instance.Dependencies)
    .Distinct()
    .Select(dependency => new { d = dependency, o = instances.Where(instance => instance.Dependencies.Contains(dependency)).SelectMany(instance => instance.Dependencies).Except(new string[] { dependency }).Distinct() })
    .Select(a => a.d + " => " + string.Join(", ", a.o));

// If you're in LINQPad
nice.Dump();

输出:

Amount => CustomerDate, AppointmentDate, SomethingElse
CustomerDate => Amount, AppointmentDate
AppointmentDate => Amount, CustomerDate, SomethingElse
SomethingElse => Amount, AppointmentDate, Something
Something => SomethingElse