Assoc Array to String & String to Assoc Array

I like coding PHP, in Perl we can change an associative array to a list then to a string. In case if we wish to do the same in PHP, we need to write some user functions for that purpose.
Here are two functions which will convert Array to String and vice-versa.

PHP:

//array to string
 function arraytostr ($array=array()) {
 
      $length = 0;
      $foreach ($array as $key => $value) {
           $keystring .= "$key ";
           $valuestring .= "$value ";
           $length++;
      }
         
      return array($length,$keystring,$valuestring);
 }
 
 //sting to array    
 function strtoarray ($length="",$keystring="",$valuestring="") {
           $keys = explode(" ",$keystring);
           $values = explode(" ",$valuestring);
           for ($i=0; $i < $length; $i++) {
         $key = $keys[$i];
         $newarray[$key] = $values[$i];
           }
         
           return $newarray;
 }