如何在 C # 中找到父目录?

我使用此代码查找调试目录

public string str_directory = Environment.CurrentDirectory.ToString();

"C:\\Users\\Masoud\\Documents\\Visual Studio 2008\\Projects\\MyProj\\MyProj\\bin\\Debug"

如何找到如下所示的父文件夹?

"C:\\Users\\Masoud\\Documents\\Visual Studio 2008\\Projects\\MyProj\\MyProj"

168951 次浏览

You might want to look into the DirectoryInfo.Parent property.

If you append ..\.. to your existing path, the operating system will correctly browse the grand-parent folder.

That should do the job:

System.IO.Path.Combine("C:\\Users\\Masoud\\Documents\\Visual Studio 2008\\Projects\\MyProj\\MyProj\\bin\\Debug", @"..\..");

If you browse that path, you will browse the grand-parent directory.

You shouldn't try to do that. Environment.CurrentDirectory gives you the path of the executable directory. This is consistent regardless of where the .exe file is. You shouldn't try to access a file that is assumed to be in a backwards relative location

I would suggest you move whatever resource you want to access into a local location. Of a system directory (such as AppData)

You can use System.IO.Directory.GetParent() to retrieve the parent directory of a given directory.

This is the most common way -- it really depends on what you are doing exactly: (To explain, the example below will remove the last 10 characters which is what you asked for, however if there are some business rules that are driving your need to find a specific location you should use those to retrieve the directory location, not find the location of something else and modify it.)

// remove last 10 characters from a string
str_directory = str_directory.Substring(0,str_directory.Length-10);
string parent = System.IO.Directory.GetParent(str_directory).FullName;

See BOL

To get a 'grandparent' directory, call Directory.GetParent() twice:

var gparent = Directory.GetParent(Directory.GetParent(str_directory).ToString());

Like this:

System.IO.DirectoryInfo myDirectory = new DirectoryInfo(Environment.CurrentDirectory);
string parentDirectory = myDirectory.Parent.FullName;

Good luck!

Edit: The normalization covered in this answer only happens when the path is used to access the file system, but not on the string itself. By contrast, this answer achieves the result and normalization purely using path strings, without using the file system at all.

I've found variants of System.IO.Path.Combine(myPath, "..") to be the easiest and most reliable. Even more so if what northben says is true, that GetParent requires an extra call if there is a trailing slash. That, to me, is unreliable.

Path.Combine makes sure you never go wrong with slashes.

.. behaves exactly like it does everywhere else in Windows. You can add any number of \.. to a path in cmd or explorer and it will behave exactly as I describe below.

Some basic .. behavior:

  1. If there is a file name, .. will chop that off:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", "..") => D:\Grandparent\Parent\

  1. If the path is a directory, .. will move up a level:

Path.Combine(@"D:\Grandparent\Parent\", "..") => D:\Grandparent\

  1. ..\.. follows the same rules, twice in a row:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", @"..\..") => D:\Grandparent\ Path.Combine(@"D:\Grandparent\Parent\", @"..\..") => D:\

  1. And this has the exact same effect:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", "..", "..") => D:\Grandparent\ Path.Combine(@"D:\Grandparent\Parent\", "..", "..") => D:\

Directory.GetParent is probably a better answer, but for completeness there's a different method that takes string and returns string: Path.GetDirectoryName.

string parent = System.IO.Path.GetDirectoryName(str_directory);
IO.Path.GetFullPath(@"..\..")

If you clear the "bin\Debug\" in the Project properties -> Build -> Output path, then you can just use AppDomain.CurrentDomain.BaseDirectory

To avoid issues with trailing \, call it this way:

  string ParentFolder =  Directory.GetParent( folder.Trim('\\')).FullName;

To get your solution try this

string directory = System.IO.Directory.GetParent(System.IO.Directory.GetParent(Environment.CurrentDirectory).ToString()).ToString();

No one has provided a solution that would work cross-form. I know it wasn't specifically asked but I am working in a linux environment where most of the solutions (as at the time I post this) would provide an error.

Hardcoding path separators (as well as other things) will give an error in anything but Windows systems.

In my original solution I used:

char filesep = Path.DirectorySeparatorChar;
string datapath = $"..{filesep}..{filesep}";

However after seeing some of the answers here I adjusted it to be:

string datapath = Directory.GetParent(Directory.GetParent(Directory.GetCurrentDirectory()).FullName).FullName;

Since nothing else I have found helps to solve this in a truly normalized way, here is another answer.

Note that some answers to similar questions try to use the Uri type, but that struggles with trailing slashes vs. no trailing slashes too.

My other answer on this page works for operations that put the file system to work, but if we want to have the resolved path right now (such as for comparison reasons), without going through the file system, C:/Temp/.. and C:/ would be considered different. Without going through the file system, navigating in that manner does not provide us with a normalized, properly comparable path.

What can we do?

We will build on the following discovery:

Path.GetDirectoryName(path + "/") ?? "" will reliably give us a directory path without a trailing slash.

  • Adding a slash (as string, not as char) will treat a null path the same as it treats "".
  • GetDirectoryName will refrain from discarding the last path component thanks to the added slash.
  • GetDirectoryName will normalize slashes and navigational dots.
  • This includes the removal of any trailing slashes.
  • This includes collapsing .. by navigating up.
  • GetDirectoryName will return null for an empty path, which we coalesce to "".

How do we use this?

First, normalize the input path:

dirPath = Path.GetDirectoryName(dirPath + "/") ?? ""; // To handle nulls, we append "/" rather than '/'

Then, we can get the parent directory, and we can repeat this operation any number of times to navigate further up:

// This is reliable if path results from this or the previous operation
path = Path.GetDirectoryName(path);

Note that we have never touched the file system. No part of the path needs to exist, as it would if we had used DirectoryInfo.