Php uses recursion to traverse the multi-dimensional array

Array ([dir] & gt; Array ([F: development test test9.14 Chanel 1-10] & gt; Array ([dir] & gt; Array ([F: examples] & gt; Array ([file] & gt; Array ([0] & gt; F: development test test9.14xianaier 1-102362_g_131_59108234.jpg 201205261903496506-php traversal recursion

Array
(
[Dir] => Array
(
[F: \ developer test \ 9.14 Chanel 1-10] => Array
(
[Dir] => Array
(
[F: \ development test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg] => Array
(
[File] => Array
(
[0] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205262133496506-1.jpg
[1] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205262133556506-2.jpg
[2] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205268244003666-3.jpg
[3] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205262134076506-4.jpg
[4] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205261904131096-5.jpg
[5] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205261904196506-6.jpg
[6] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205261_000000006-7.jpg
[7] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205261904116506-8.jpg
[8] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 201205261904116506-9.jpg
[9] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 2362_g_1310859108234.jpg
[10] => F: \ development and testing \ test \ 9.14 Chanel 1-10 \ 2362_g_1310859108234.jpg \ 2362_g_131_59108234.jpg.txt
)

) [F: \ development test \ 9.14 Chanel 1-10 \ 2559_g_1353134153950.jpg] => Array ([file] => Array ([0] => F: \ development test \ 9.14 Chanel 1-10 \ 2559_g_1353132133950.jpg \ large [1] => F: \ development test \ 9.14 Chanel 1-10 \ 2559_g_1353132133950.jpg \ large [2] => F: \ development test \ 9.14 Chanel 1-10 \ 2559_g_1353132133950.jpg \ large [3] => F: \ development test \ 9.14 Chanel 1-10 \ 2559_g_1353132133950.jpg \ large [4] => F: \ development test \ 9.14 Chanel 1-10 \ 2559_g_1353132133950.jpg \ large [5] => F: \ development test \ 9.14 Chanel 1-10 \ 2559_g_1353132133950.jpg \ small) [F: \ development test \ 9.14 Chanel 1-10 \ new folder] => Array ([dir] => Array ([F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg] => Array ([file] => Array ([0] => F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg \ 201210102219156516grams crocodile pattern (silver clip-1.jpg [1] => F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg \ 201210102219156516grams crocodile pattern (silver clip-2.jpg [2] => F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg \ 201210102219166516gram crocodile pattern (silver clip-3.jpg [3] => F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg \ 201210102219176516grams crocodile pattern (silver clip-4.jpg [4] => F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg \ 201210102219176516grams crocodile pattern (silver clip-5.jpg [5] => F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg \ 201210102219186516grams crocodile pattern (silver clip-6.jpg [6] => F: \ development test \ 9.14 Chanel 1-10 \ new folder \ 2558_G_1349878776638.jpg \ 201210102219186516grams crocodile pattern (silver clip-7.jpg [7] => F: \ development test \ 9.14 Chanel 1-10 \ create a folder \ 2558_G_1349878776638.jpg \ 2558_G_1349878776638.jpg) [F: \ development test \ 9.14 Chanel 1-10 \ new folder \ shiasd] => Array ())))))

)
Please help me recursively return all the key values of the above array to a one-dimensional array.