C# 修改檔案或資料夾權限：為指定使用者與群組新增完全控制權限

程式碼片段

// 給 Excel 檔案新增 "Everyone,Users" 群組完全控制權限
FileInfo fi = new FileInfo(excelPath);
FileSecurity fileSecurity = fi.GetAccessControl();
fileSecurity.AddAccessRule(new FileSystemAccessRule("Everyone", FileSystemRights.FullControl, AccessControlType.Allow));
fileSecurity.AddAccessRule(new FileSystemAccessRule("Users", FileSystemRights.FullControl, AccessControlType.Allow));
fi.SetAccessControl(fileSecurity);

// 給 Excel 檔案所在目錄新增 "Everyone,Users" 群組完全控制權限
DirectoryInfo di = new DirectoryInfo(Path.GetDirectoryName(excelPath));
DirectorySecurity dirSecurity = di.GetAccessControl();
dirSecurity.AddAccessRule(new FileSystemAccessRule("Everyone", FileSystemRights.FullControl, AccessControlType.Allow));
dirSecurity.AddAccessRule(new FileSystemAccessRule("Users", FileSystemRights.FullControl, AccessControlType.Allow));
di.SetAccessControl(dirSecurity);

使用 FileInfo/DirectoryInfo 取得 FileSecurity/DirectorySecurity，新增 FileSystemAccessRule 規則並套用。