Regex: find whatever comes after one thing before another thing

Question

I want to find anything that comes after s= and before & or the end of the string. For example, if the string is

t=qwert

Answer 1

The simplest way to do this is with a selector s=([^&]*)&. The inside of the parentheses has [^&] to prevent it from grabbing hello&p=3 of there were another field after p.