A method of generating tree in reference implementation in PHP

This article mainly introduces the introduction of PHP in the implementation of tree generation method, interested in the reference of friends, I hope to help you.

Are you still wasting your time and wasting your memory recursively traversing infinite pole categories, reading this article, I think you should change.

This is what I saw on the Oschina a very streamlined PHP infinite pole classification Spanning tree method, skillfully in the reference, sorting and sharing.

The code is as follows:

function Generatetree ($items) {    $tree = array ();    foreach ($items as $item) {        if (isset ($items [$item [' pid]]) {$items [            $item [' pid ']][' son '] [] = & $items [$ item[' id '];        } else{            $tree [] = & $items [$item [' id '];        }    }    return $tree;}  $items = Array (1 = = Array (    ' id ' = = 1, ' pid ' = 0, ' name ' = ' Anhui '), 2 = =    Array (' id ' = = 2, ' pid ') = 0, ' name ' = ' Zhejiang province ',    3 = = Array (' id ' = 3, ' pid ' = = 1, ' name ' = ' Hefei '),    4 = = Array (' ID ' = 4, ' pid ' = 3, ' name ' = = ' Changfeng County '),    5 = = Array (' id ' = = 5, ' pid ' = 1, ' name ' = ' Anqing '),;p rint _r (Generatetree ($items));

You can see the results printed below:

The code is as follows:

Array ([0] = = Array ([id] = 1 [pid] = 0 [name] = = Anhui Province                            [Son] = array ([0] = = Array (                            [ID] + 3 [PID] + 1 [name] = = Hefei City                                        [Son] = array ([0] = = Array                                            ([id] = 4                                 [PID] = 3 [name] = Changfeng County)                            )) [1] = = Array (                        [ID] + 5 [PID] + 1 [name] = = Anqing   )              )) [1] = = Array ([id] = 2 [PID] + 0 [name] (Zhejiang Province))

The spanning tree method above can also be reduced to 5 rows:

The code is as follows:

function Generatetree ($items) {    foreach ($items as $item)        $items [$item [' pid ']][' son '] [$item [' id ']] = &$ items[$item [' id ']];    return Isset ($items [0][' son '])? $items [0][' son ']: Array ();}

The above-mentioned method of tree-shaped structure of infinite pole classification data is worthy of reference. But I think the actual use of this code is not obvious ah, you want to take out the formatted tree data or recursive AH:

The code is as follows:

/** * How to fetch data formatted tree data */$tree = Generatetree ($items); function Gettreedata ($tree) {    foreach ($tree as $t) {        echo $t [' Name ']. ' <br> ';        if (Isset ($t [' son '])) {            gettreedata ($t [' son ']);}}}    Gettreedata ($tree);

Summary : The above is the entire content of this article, I hope to be able to help you learn.

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