104) PHP, directory tree output

1 use a specific number of indents to achieve tree-like purposes!  2 Core issues, calculate the number of indents required!  3 indentation level, consistent with recursive call depth. The indentation level of the found file is +1whenever a first-level recursive operation is performed; 4 Syntax Implementation: 5     Adds a parameter that represents the depth level of the current function call, whenever recursion +1;

104) PHP, directory tree output