NOC is only enough to get new visa

I am going to leave the current employer with the NOC to join a new sponsor. To get the new visa, only NOC is enough or it is must to present the PRO of previous company to the ROP?

My wife and children visas also must be cancelled together with me when I leave for new visa?

My kids are going to school now and I want them to be here till I come with new visa and is it possible them to be here continuesly with old visa  till  it  is expired?

http://timesofoman.com/article/91187/Ti … -visa-rule

NOC with your future employer name and complete details about with CR COPY enough for transfer of local visa same will be applicable to your family.
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