Consider this array in PHP:
$list = array('apple','orange','alpha','bib','son','green','odd','soap');
How can i get a sub array of elements start with letter 'a' or 's' ?
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6 Answers
2 Comments
Cups
$a = preg_grep('#^a|s#', array_map('strtolower', $list)); Just in case you have mixed case (make apple Apple in your test). +1 for posting a proper PHP array we can just copy and use. Thoughtful.
Cups
Ah, well it seems to, then again this is better $a = preg_grep('#^a|s#i', $list); <-use the i regex switch
Check out array_filter here: http://www.php.net/manual/en/function.array-filter.php
$list = array_filter($list, function ($a) { return $a[0] == 'a' || $a[0] == 's'; });
Comments
$sublist = array();
for ($i = 0; $i < count($list); $i++) {
if ($list[$i][0] == 'a' or $list[$i][0] == 's') {
$sublist[] = $list[$i];
}
}
2 Comments
benqus
$list[$i][0] <-- can you do that in PHP? =O Never thought of that one before... =] Nice! =]
Hammerite
@benqus: Yes, PHP allows you to give a string offset using the array-offset notation. Like any PHP operation involving strings, it won't behave well if you have a string in a multi-byte character set.
for ($i =0; $i < count($list); $i++) {
if (substr($list[i], 1) == "a" || substr($list[i], 1) == "s") {
//put it in an other array
}
}
Comments
<?php
$list = array('apple','orange','alpha','bib','son','green','odd','soap');
$tmp_arr = array(); foreach ($list as $t) { if (substr($t, 0, 1) == 'a' || substr($t, 0, 1) == 's') { $tmp_arr[] = $t; } }
print_r($tmp_arr);
?>
//output: Array ( [0] => apple [1] => alpha [2] => son [3] => soap )
1 Comment
mickmackusa
This poorly formatted answer is missing its explanation.
This is one way of doing it:
$list = array('apple','orange','alpha','bib','son','green','odd','soap');
$a = array();
$s = array();
for ($i = 0; $i < count($list); $i++)
{
if (substr($list[$i], 0, 1) == "s")
{
$s[$i] = $list[$i];
}
else if (substr($list[$i], 0, 1) == "a")
{
$a[$i] = $list[$i];
}
}
