I am trying to match a string to a regex pattern, but have some problems.

My string could have 3 forms:

1. [dbo].[Start]
2. dbo.Start
3. Start

This is my regex:

"^((\[)?dbo(\])?)?(\.)?(\[)?Start(\])?$"

All 3 forms returns success but there are some more options such as: [dboStart or dbo[Start

I know that this is because it is optional, but how could I make dependencies when making optional, so that if one optional has value then the second optional must have a value too.

Could you help me please to fix this?

Thanks.