In case of = in the event of

• In case of fire, ring the alarm bell.
• In case of any difficulty, please contact me over the phone.
• In case of any complications we sought the opinion of senior doctors ( past)

In any case = whatever happens or may have happened.

• He will not help me in any case.
• In any case we are not going to give in to his pressure tactics.
• In any case the project should be completed within the stipulated time.

In no case = under no circumstances.

• In no case I will accept his proposal.
• In no case the proposal is going to be viable without the support and cooperation of the local residents.

In this case / in that case = if this /that happens, has happened, should happen.

• In that case , you may phone the police.
• In this case, it is advisable to utilise our own funds for investments ; because financial institutions are charging exorbitant rate of interest.