Why can't I write IO.Directory.GetFiles?

问题

I come from a VB.Net environment, where using Imports System and then IO.Directory.GetFiles(...) works.

On the other hand, it seems that using System; is not sufficient to write use IO.Directory without prefixing it with System.. The only workaround seems to be using IO = System.IO;

Why?

---

Example code:

using System;
using System.IO;

namespace Test {
    class Program {
        static void Main(string[] args) {
            System.Console.WriteLine(IO.Directory.GetFiles(System.Environment.CurrentDirectory)[0]);
        }
    }
}

Edit: My question is not what should I do to get my code working, but specifically "why cant I write IO.Directory.GetFiles ??"

回答1:

Add

using System.IO;

and you'll have the behavior you expect. C# does not make child namespaces available without a using directive (or full qualification.)

回答2:

The thing you are talking about is not posssible in C# that might be diffrence between C# and vb.NET.

If you are converting vb.Net code to C# than make use of this site will help you lot

vb.net to c#

Code fo ryou

System.IO.Directory.GetFiles(...)

or add

using System.IO;

will do for you

来源：https://stackoverflow.com/questions/9433012/why-cant-i-write-io-directory-getfiles