How do I replace a specific occurrence of a string in a string?

Question

I have a string which may contain \"title1\" twice in it.

e.g.

server/api/shows?title1=its always sunny in philadelphia&title1=breaking ba

Answer 1

You could perhaps make use of a negative lookahead:

title1(?!.*title1)

And replace with title2.

See how it's working here.