Unlimited category and disk file directory Printing

1. Unlimited Classification
-- Create a table
Create Table it_category (
Cat_id int unsigned primary key auto_increment,
Cat_name varchar (50) default '',
Sort_order int default 0,
Parent_id int unsigned
);
-- Insert record
Insert into it_category values (75, 'classification KKK ', 50, 0 );
Insert into it_category values (12, 'classification fff', 50, 75 );
Insert into it_category values (77, 'classification aaa', 50, 75 );
Insert into it_category values (34, 'classification XXX', 50, 12 );
Insert into it_category values (35, 'classification hhh', 50, 12 );
Insert into it_category values (9, 'classification qqq', 50, 77 );
Insert into it_category values (28, 'classification jjj ', 50, 35 );
Insert into it_category values (19, 'category mmm', 50, 35 );

<? PHP
// 1. This is what the teacher said
// First, obtain all the classified data
Mysql_connect ('127. 0.0.1: 808080', 'root', '1234abcd ');
$ SQL = "select * From itcast_shop.it_category where 1 order by sort_order ";
$ Result = mysql_query ($ SQL );
While ($ ROW = mysql_fetch_assoc ($ result )){
$ List [] = $ row;
}

// Then, call the recursive lookup Function
$ Tree = gettree ($ list, 0, 0 );

// Finally, traverse and display
Foreach ($ tree as $ row ){
Echo str_repeat ('& nbsp;', $ row ['deep ']);
Echo $ row ['cat _ name'];
Echo '<br> ';
}

Function gettree ($ arr, $ p_id, $ deep = 0 ){
Static $ tree = array ();
Foreach ($ arr as $ row ){
If ($ row ['parent _ id'] = $ p_id ){
$ Row ['deep '] = $ deep;
$ Tree [] = $ row;
// Locate a qualified record and recursively look for it in a deeper level! Search and return to continue this foreach
Gettree ($ arr, $ row ['cat _ id'], $ deep + 1 );
}
}

// The result is returned after the foreach operation is completed.
Return $ tree;
}


--------------------------------- Change the method ------------------------------


<? PHP

// 2. A friend is confused by the return $ tree of the recursive function;
// Actually, this return is useless after recursion, because $ tree is already a static local variable.
// Return indicates that the foreach execution is complete and the queried data is returned.
// * We Don't Need To return. use $ tree as a super global variable.
// First, obtain all the classified data
Mysql_connect ('127. 0.0.1: 808080', 'root', '1234abcd ');
$ SQL = "select * From itcast_shop.it_category where 1 order by sort_order ";
$ Result = mysql_query ($ SQL );
While ($ ROW = mysql_fetch_assoc ($ result )){
$ List [] = $ row;
}

// Then, call the recursive lookup Function
Gettree ($ list, 0, 0 );

// Finally, traverse and display
Foreach ($ tree as $ row ){
Echo str_repeat ('& nbsp;', $ row ['deep ']);
Echo $ row ['cat _ name'];
Echo '<br> ';
}

Function gettree ($ arr, $ p_id, $ deep = 0 ){
Foreach ($ arr as $ row ){
If ($ row ['parent _ id'] = $ p_id ){
$ Row ['deep '] = $ deep;
$ Globals ['tree'] [] = $ row;
// Locate a qualified record and recursively look for it in a deeper level! Search and return to continue this foreach
Gettree ($ arr, $ row ['cat _ id'], $ deep + 1 );
}
}
}




Ii. Use PHP to print the disk file directory
<? PHP
Function dirtree ($ path, $ deep = 0 ){
$ Dir_handle = opendir ($ PATH );

While ($ file = readdir ($ dir_handle ))! = False ){
If ($ file = '.' | $ file = '..'){

} Else {
If (is_dir ($ path. '/'. $ file )){
Echo str_repeat ('& nbsp;', $ deep );
Echo '+', $ file, '<br/> ';
Dirtree ($ path. '/'. $ file, $ deep + 1 );
} Else {
Echo str_repeat ('& nbsp;', $ deep );
Echo $ file, '<br/> ';
}
}
}
}

$ Path = 'd: \ amp \ apache \ htdocs \ study ';
Dirtree ($ PATH );

Unlimited category and disk file directory Printing