<?php
$str='fdsf-sd{spider:-}ds{spider:wb}f-dsf';
preg_match_all('/\{spider:.*?\}/',$str,$matches);
$arr=$matches[0];
$str=preg_replace('/\{spider:.*?\}/','*',$str);
$str=str_replace('-','',$str);
$pos = 0;
$count=0;
while($n = strpos($str,"*",$pos))
{
$pos =$n+1;
$str=substr_replace($str,$arr[$count],$n,1);
$count++;
}
echo $str;