getting directories list and sub-directories for each directory into $catch[][] ???

[Fking]

i have the array $catch[] which has all names of sub-directories in a directory
but i want to make it contain the names of sub-directories for each sub-directory it already has
in $catch[][]

for ($r=0; $r < count($catch); $r++)
{
 $sub_dirs=$nav_file . $catch["$r"];
//$nav_file is the /path/to/thedir/
//$catch[$r]is the name of the dir

 if ( $dh = opendir($sub_dirs))
        {
          while ( false !== ( $file = readdir($dh) ) )
           {if ( strpos($file, '.')===false  && $file != '.' && $file != '..' &&  $file !='heart' )  $catch[$r][] = $file;   }

     }

 rewinddir($dh);
closedir($dh);

  } 

but i get this error
Fatal error: [] operator not supported for strings

[Weedpacket]

Without knowing where $catch is being generated, or the results of such debugging tasks as checking its value, all I can guess is that $catch[$r] is not an array element, but a character from a string (the error message is saying that $catch is a string, not an array).

[Fking]

the $catch[] array
Array ( [0] => TamaFura [1] => download [2] => funpics [3] => movies [4] => pics [5] => stories )

it's generated with this code

 if ( $dh = opendir($nav_file))
        {
          while ( false !== ( $file = readdir($dh) ) )
           {if ( strpos($file, '.')===false  && $file != '.' && $file != '..' &&  $file !='heart' &&  $file != "$ex_dir1" &&  $file !="$ex_dir2" &&  $file !="$ex_dir3" &&  $file !="$ex_dir4"  &&  $file !="$ex_dir5")  $catch[] = $file;   }

     }

 rewinddir($dh);
closedir($dh);

so, the array $catch[] contains directory names
I want each $catch[0][], $catch[1][], $catch[2][]
to contain the subdirectories of each alredy listed directory

except with the code from the first post, where i use $catch[$r][]=$file
i tried with $$catch[$r][] in order to make new arrays each with the name with dir, but still get error, this time "Fatal error: Cannot use [] for reading"
in short: i want to get the structure of directory and all sub-directories of that directory in one array
the dir names from the main directory in $catch[]
and the dir names of each sub-directory in $catch[key][]

thank you

[Weedpacket]

So $catch starts out being an array of strings (directory names), and you want to replace them with arrays. So you're going to have to get those strings out and put arrays in.

foreach($catch as $directory=>$name)
{
$catch[$directory] = array();
// $name is the name of the subdirectory
// whose contents you can now put in $catch[$directory]
}