php - Extract from string using regex -

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• how use square bracket inside php regex class? 5 answers

i need extract piece of string. have extract system.cpu.util[,idle] or net.if.out[eth2] respectively idle , eth2.

i don't know how detect correcty [ , ] can me?

here manual preg_match

var= net.if.out[eth2] preg_match('/\[,?(.*?)\]/', $var, $match); print match[1];