- substr: documentation ( source)
- strpos: documentation ( source)
<?php
$p_field_type = "select{m,f}";
if(strpos($p_field_type, "{")!==FALSE && strpos($p_field_type, "}")!==FALSE) { echo "huzza!"; } else { echo "nuuuuh!"; }
echo "\n";
echo substr($p_field_type,
strpos($p_field_type, "{") + 1,
strpos($p_field_type, "}") - strpos($p_field_type, "{") - 1);