在C#中，我们有以下几种方式获取程序当前目录：

            Console.WriteLine(System.IO.Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location));
            Console.WriteLine(System.AppDomain.CurrentDomain.BaseDirectory);
            Console.WriteLine(System.Environment.CurrentDirectory);
            Console.WriteLine(System.IO.Directory.GetCurrentDirectory());
            Console.WriteLine(Environment.CurrentDirectory);

输出：

D:\MyTool\MyWorkRelated\C#_Tool\Defect Process Tool\DefectExcelProcesTool\DefectExcelProcesTool\bin\Debug
D:\MyTool\MyWorkRelated\C#_Tool\Defect Process Tool\DefectExcelProcesTool\DefectExcelProcesTool\bin\Debug\
D:\MyTool\MyWorkRelated\C#_Tool\Defect Process Tool\DefectExcelProcesTool\DefectExcelProcesTool\bin\Debug
D:\MyTool\MyWorkRelated\C#_Tool\Defect Process Tool\DefectExcelProcesTool\DefectExcelProcesTool\bin\Debug
D:\MyTool\MyWorkRelated\C#_Tool\Defect Process Tool\DefectExcelProcesTool\DefectExcelProcesTool\bin\Debug

亲测可以代码正确。