How can rename a database completely?

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SQL-Server-2012

hello.
i decide to rename my database. i write following:

ALTER DATABASE MyDB SET SINGLE_USER WITH ROLLBACK IMMEDIATE 

ALTER DATABASE  MyDB modify file(Name=N'MyDB',NewName=N'TaskManager')
go
alter database MyDB modify file(Name=N'MyDB_log',newName=N'TaskManager_log')
go

exec sp_detach_db @dbname=N'MyDB'
go
sp_configure 'xp_cmdshell',1
go
reconfigure with override
go

exec xp_cmdshell 'RENAME "E:\MyDB.mdf","TaskManager.mdf"'
go
exec xp_cmdshell 'RENAME "E:\MyDB_log.ldf","TaskManager_log.ldf"'
go

create database TaskManager ON
(Filename=N'E:\TaskManager.mdf'),
(Filename=N'E:\TaskManager_log.ldf')
for attach
go
alter database TaskManager set multi_user
go

this script renames my database files (mdf and ldf) correctly.but my database has 53 .ndf files.
their names not changed yet. now i have two question:
1-Is it harmfull for my database?(.ndf files names not changed according to .mdf file)
2- how can i rename logical name and physical name and .ndf file name at the same time?
thanks alot