gistfile1.php

$template = 'abc{def}gh{ijk}lmn';
$data['def']='DEF你妹';
$data['ijk']='IJK壕';
        preg_match_all('/(?<=\{)([^\}]*?)(?=\})/' , $template , $arr);
        foreach ($arr[0] as &$item) {
                   $template=      str_replace('{' . $item . '}', $data[$item], $template);
          
        }
echo $template;