AppDomain.CurrentDomain.BaseDirectory

在winform中的OnPaint事件中，AppDomain.CurrentDomain.BaseDirectory得到的是下面这个路径

C:Program Files (x86)Microsoft Visual Studio2017ProfessionalCommon7IDE

Application.ExecutablePath得到的是C:Program Files (x86)Microsoft Visual Studio2017ProfessionalCommon7IDEdevenv.exe

file:///C:/Users/clu/AppData/Local/Microsoft/VisualStudio/15.0_74da2886/ProjectAssemblies/us6sa4js01/Accor.Windows.Forms.dll

https://stackoverflow.com/questions/837488/how-can-i-get-the-applications-path-in-a-net-console-application

System.Reflection.Assembly.GetExecutingAssembly().Location¹

Combine that with System.IO.Path.GetDirectoryName if all you want is the directory.

¹As per Mr.Mindor's comment:
System.Reflection.Assembly.GetExecutingAssembly().Location returns where the executing assembly is currently located, which may or may not be where the assembly is located when not executing. In the case of shadow copying assemblies, you will get a path in a temp directory. System.Reflection.Assembly.GetExecutingAssembly().CodeBase will return the 'permanent' path of the assembly.

https://stackoverflow.com/a/841320/3782855

AppDomain.CurrentDomain.BaseDirectory

Don't use this. The BaseDirectory can be set at runtime. It is not guaranteed to be correct (like the accepted answer is).

entryAssembly.GetSatelliteAssembly

System.IO.FileNotFoundException: Could not find file 'file:///C:/Users/clu/AppData/Local/Microsoft/VisualStudio/15.0_74da2886/ProjectAssemblies/dgz79z6i01/en-US/Accor.Windows.Forms.resources.DLL'.
File name: 'file:///C:/Users/clu/AppData/Local/Microsoft/VisualStudio/15.0_74da2886/ProjectAssemblies/dgz79z6i01/en-US/Accor.Windows.Forms.resources.DLL'

How do I get the path of the assembly the code is in?

使用codebase是最准的

I've defined the following property as we use this often in unit testing.

public static string AssemblyDirectory
{
    get
    {
        string codeBase = Assembly.GetExecutingAssembly().CodeBase;
        UriBuilder uri = new UriBuilder(codeBase);
        string path = Uri.UnescapeDataString(uri.Path);
        return Path.GetDirectoryName(path);
    }
}

The Assembly.Location property sometimes gives you some funny results when using NUnit (where assemblies run from a temporary folder), so I prefer to use CodeBase which gives you the path in URI format, then UriBuild.UnescapeDataString removes the File:// at the beginning, and GetDirectoryName changes it to the normal windows format.