using System;
using System.IO;

// Get the current directory and make it a DirectoryInfo object.
// Do not use Environment.CurrentDirectory, vistual studio 
// and visual studio code will return different result:
// Visual studio will return @"projectDir\bin\Release\netcoreapp2.0\", yet 
// vs code will return @"projectDir\"
var currentDirectory = new DirectoryInfo(AppDomain.CurrentDomain.BaseDirectory);

// On windows, the current directory is the compiled binary sits,
// so string like @"bin\Release\netcoreapp2.0\" will follow the project directory. 
// Hense, the project directory is the great grand-father of the current directory.
string projectDirectory = currentDirectory.Parent.Parent.Parent.FullName;

.Parent.Parent.Parent.Parent.FullName Directory.GetParent (Directory.GetCurrentDirectory ())

会给你项目目录。

using System;
using System.IO;

// This will get the current WORKING directory (i.e. \bin\Debug)
string workingDirectory = Environment.CurrentDirectory;
// or: Directory.GetCurrentDirectory() gives the same result

// This will get the current PROJECT bin directory (ie ../bin/)
string projectDirectory = Directory.GetParent(workingDirectory).Parent.FullName;

// This will get the current PROJECT directory
string projectDirectory = Directory.GetParent(workingDirectory).Parent.Parent.FullName;

好吧，2021年，有点晚了…但我在许多项目中发现的所有可能性都让我很恼火:

bin /调试 bin / x86 -调试 bin /调试- net5 0-windows。 ...

来吧……我只需要一行程序(或几乎)来处理测试单元中的一些文件;我需要在所有过去、现在、(可能是未来)的项目中使用它。

因此，如果项目名称与它所在的相对文件夹相同:

使用程序集名称选择项目根文件夹名称; 回去找，直到找到那个名字。

代码示例:

string appName = Assembly.GetExecutingAssembly().GetName().Name;
var dir = new DirectoryInfo(Environment.CurrentDirectory);
while (dir.Name != appName) {
  dir = Directory.GetParent(dir.FullName);
}
return dir.FullName;

using System;
using System.IO;

// Get the current directory and make it a DirectoryInfo object.
// Do not use Environment.CurrentDirectory, vistual studio 
// and visual studio code will return different result:
// Visual studio will return @"projectDir\bin\Release\netcoreapp2.0\", yet 
// vs code will return @"projectDir\"
var currentDirectory = new DirectoryInfo(AppDomain.CurrentDomain.BaseDirectory);

// On windows, the current directory is the compiled binary sits,
// so string like @"bin\Release\netcoreapp2.0\" will follow the project directory. 
// Hense, the project directory is the great grand-father of the current directory.
string projectDirectory = currentDirectory.Parent.Parent.Parent.FullName;

最好的解决方案

string PjFolder1 =
    Directory.GetParent(AppDomain.CurrentDomain.BaseDirectory).
        Parent.Parent.FullName;

其他解决方案

string pjFolder2 = Path.GetDirectoryName(Path.GetDirectoryName(Path.GetDirectoryName(
                System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase)));

测试它，AppDomain.CurrentDomain.BaseDirectory在过去的项目中为我工作，现在我得到调试文件夹....所选的好答案就是不行!

//Project DEBUG folder, but STILL PROJECT FOLDER
string pjDebugFolder = AppDomain.CurrentDomain.BaseDirectory;

//Visual studio folder, NOT PROJECT FOLDER
//This solutions just not work
string vsFolder = Directory.GetCurrentDirectory();
string vsFolder2 = Environment.CurrentDirectory;
string vsFolder3 = Path.GetFullPath(".\\");   

//Current PROJECT FOLDER
string ProjectFolder = 
    //Get Debug Folder object from BaseDirectory ( the same with end slash)
    Directory.GetParent(pjDebugFolder).
    Parent.//Bin Folder object
    Parent. //Project Folder object
    FullName;//Project Folder complete path