Check if a string contains a certain number

Question

I have a string

8,7,13,14,16

Whats the easiest way to determine if a given number is present in that string?

$numberA = \"1         


        

Answer 1

if (strpos(','.$string.',' , ','.$numberA.',') !== FALSE) {
    //found
}

Notice guard ',' chars, they will help to deal with '13' magic '1, 2, 133' case.