Find first occurence of substring before a certain position
In PHP, if I have a long string, IE 10'000 chars, how would you suggest I go about finding the first occurence of a certain string before and after a given position.
IE, if I have the string:
BaaaaBcccccHELLOcccccBaaaaB
I can use strpos to find the position of HELLO. How could I then go about finding the position of the first occurence of B before HELLO and the first occurence of B after HELLO?
Given the position…
To find the first occurrence before, you can take the substr() before the match and use strrpos() .
To find the first occurrence after, you can still use strpos() and set the offset parameter.
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