RegEx to validate string with alphabets and for opening and closing parentheses if available with alphabets in it, is not working.
^[a-zA-Z]([a-zA-Z '-.]|(?<=\[)[A-Za-z]+(?=\]))*$
Valid String :- Demo test-demo's [Test-Demo]
Valid String :- String's.(SomeStringHere)[SomeStringHere]
Invalid String :- 'String()'
Invalid String :- 'String)('
Invalid String :- 'String[]'
Invalid String :- 'String]['