Regular expressions in arrays

lucianoes

    Dear friends,
    I know I can use 'preg_match' to find regular expressions inside any given string or variable, but I can't figure out how I can find them inside arrays. More specifically, I have an array with a lot of names and I want to check if any of these names is "John".

    Thank you,
    Luciano ES
    Santos - SP - Brasil

[deleted]

An array is just a collection of vars,
so you can just loop through the array and run the regexp on each element seperately.

lucianoes

    Hmmm... that is what I am doing. But as a fan of short and compact code, I was hoping to find a shorter way.

    Thank you,
    Luciano ES
    Santos - SP - Brasil

vsego

preg_match($pattern, implode($separator, $array))

$separator has to be something that is not a substring of $pattern.

Still, while this looks more compact, it produces ugly overhead (both memory and processing one). I'd go after Vincent's solution.

Besides, why is foreach() preg_match(); NOT compact enough?

lucianoes

    I was completely unaware of the foreach() function. I read about it and found it a little complicated. What I was doing was:

$a=0;
for ($elem=0; $elem<40; $elem++)
{
global $a;
if ("John" == $list_of_names[$elem])
{$a++; break;}
else
{$dummy="do_nothing";}
}
if (a>0) {print "John is in the list";}
else {print "John is not in the list";}

    See? Kind of long, isn't it? I guess you guys misinterpreted what I wanted, because I found out I can do all that with just a couple of lines, using 'in_array'. There, problem solved!

    Thank you for your help, I am going to give that 'foreach' function another look and see what I can learn from it.

    Cheers,
    Luciano ES
    Santos - SP - Brasil

vsego

foreach ($array as $key=>$value) something($key, $value);

This means: "For each item of $array there is key - put it in variable $key - and value - put it in variable $value. Then (still for each item) call something($key, $value)."

If key is not important, you can use
foreach ($array as $value) something($value);

I use foreach() eversince it was introduced. Great little thing! :-)

Good luck