c # to the file / folder management user rights

 public  class PermissionManager 
    { 
        ///  <Summary> 
        /// add users to a file, the user full control everyone group
         ///  </ Summary> 
        ///  <param name = "filePath"> </ param> 
        public  static  void AddSecurityControll2File ( String filePath) 
        { 

            // get the file information of 
            the FileInfo the fileInfo = new new the FileInfo (filePath);
             // get access to the file 
            System.Security.AccessControl.FileSecurity FileSecurity = fileInfo.GetAccessControl ();
             // add user group ereryone access full control rules
            fileSecurity.AddAccessRule ( new new the FileSystemAccessRule ( " the Everyone " , FileSystemRights.FullControl, AccessControlType.Allow));
             // add access rules Users user group Full Control permissions 
            fileSecurity.AddAccessRule ( new new the FileSystemAccessRule ( " Users " , FileSystemRights.FullControl, AccessControlType .Allow));
             // set access permissions 
            fileInfo.SetAccessControl (FileSecurity); 
        } 

        ///  <Summary> 
        /// folders adding users, full control of the user group everyone
         ///  </ Summary> 
        ///  <param name = "dirPath"> </param>
        public  static  void AddSecurityControll2Folder ( String dirpath) 
        { 
            // get folder information 
            DirectoryInfo dir = new new DirectoryInfo (dirpath);
             // get all access to the folder 
            System.Security.AccessControl.DirectorySecurity dirSecurity = dir.GetAccessControl (AccessControlSections.All );
             // set file ACL inheritance 
            InheritanceFlags the inherits = InheritanceFlags.ContainerInherit | InheritanceFlags.ObjectInherit;
             // add access rules ereryone user group full control permissions to 
            the FileSystemAccessRule everyoneFileSystemAccessRule = new newThe FileSystemAccessRule ( " the Everyone " , FileSystemRights.FullControl, the Inherits, PropagationFlags.None, AccessControlType.Allow);
             // add access rules Users user group Full Control permissions to 
            the FileSystemAccessRule usersFileSystemAccessRule = new new the FileSystemAccessRule ( " Users " , FileSystemRights.FullControl, the Inherits, PropagationFlags.None, AccessControlType.Allow);
             BOOL the isModified = to false ; 
            dirSecurity.ModifyAccessRule (AccessControlModification.Add, everyoneFileSystemAccessRule, OUT the isModified);
            dirSecurity.ModifyAccessRule (AccessControlModification.Add, usersFileSystemAccessRule, OUT isModified);
             // set access permissions 
            dir.SetAccessControl (dirSecurity); 
        } 


        ///  <the Summary> 
        /// remove a user's permissions for the folder
         ///  < / Summary> 
        ///  <param name = "dirName"> </ param> 
        ///  <param name = "username"> </ param> 
        static  void removePermissions ( String dirName, String username) 
        { 
            String User = the System.Environment + .UserDomainName " \\ " + username;
            DirectoryInfo dirinfo = new DirectoryInfo(dirName);
            DirectorySecurity dsec = dirinfo.GetAccessControl(AccessControlSections.All);

            AuthorizationRuleCollection rules = dsec.GetAccessRules(true, true, typeof(System.Security.Principal.NTAccount));
            foreach (AccessRule rule in rules)
            {
                if (rule.IdentityReference.Value == user)
                {
                    bool value;
                    dsec.PurgeAccessRules(rule.IdentityReference);
                    dsec.ModifyAccessRule (AccessControlModification.RemoveAll, rule, OUT value); 
                } 
            } 
        } 

        ///  <the Summary> 
        /// project using the folder reserved only everyone permission, which allows users to read, but not write
         /// by the way, the code is the result of a special permissions to a folder, point into high-level look, you will find this child child and write access to special privileges are the same
         ///  </ the Summary> 
        ///  <param name = "dirName"> </ param> 
        public  static  void OnlyKeepEveryonePermissionsWithWriteNotAllowed ( String dirName) 
        { 
            the DirectoryInfo DirInfo = new new  the DirectoryInfo (dirName);
            a DirectorySecurity objSecObj = dirinfo.GetAccessControl();
            AuthorizationRuleCollection acl = objSecObj.GetAccessRules(true, true,
                                                        typeof(System.Security.Principal.NTAccount));
            objSecObj.SetAccessRuleProtection(true, false); //to remove inherited permissions
            foreach (FileSystemAccessRule ace in acl) //to remove any other permission
            {
                objSecObj.PurgeAccessRules(ace.IdentityReference);  //same as use objSecObj.RemoveAccessRuleSpecific(ace);
            }
            InheritanceFlags inherits = InheritanceFlags.ContainerInherit | InheritanceFlags.ObjectInherit;
            FileSystemAccessRule everyoneFileSystemAccessRule = new FileSystemAccessRule("Everyone", FileSystemRights.ReadAndExecute | FileSystemRights.ListDirectory | FileSystemRights.Read, inherits, PropagationFlags.None, AccessControlType.Allow);
            FileSystemAccessRule everyoneFileSystemAccessRule2 = new FileSystemAccessRule("Everyone", FileSystemRights.Write, AccessControlType.Deny);
            bool isModified = false;
            objSecObj.ModifyAccessRule(AccessControlModification.Add, everyoneFileSystemAccessRule2, out isModified);
            objSecObj.ModifyAccessRule(AccessControlModification.Add, everyoneFileSystemAccessRule, out isModified);
            dirinfo.SetAccessControl(objSecObj);
        }
    }