PHP學習
--
-- 表的結構 `tp_likecate`
--
CREATE TABLE IF NOT EXISTS `tp_likecate` (
 `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
 `catename` varchar(24) NOT NULL,
 `path` varchar(10) NOT NULL,
 `fullpath` varchar(20) NOT NULL,
 PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=9 ;

PHP學習
--
-- 轉存表中的數據 `tp_likecate`
--
INSERT INTO `tp_likecate` (`id`, `catename`, `path`, `fullpath`) VALUES
(1, '手機', '', ',1'),
(2, '功能手機', '1', '1,2'),
(3, '老人手機', '1,2', '1,2,3'),
(4, '兒童手機', '1,2', '1,2,4'),
(5, '智能手機', '1', '1,5'),
(6, 'android手機', '1,5', '1,5,6'),
(7, 'IOS手機', '1,5', '1,5,7'),
(8, 'WinPhoto手機', '1,5', '1,5,8');

PHP學習
<?php 
$db_host = 'localhost';
$db_user = 'root';
$db_password = '';
$db_name = 'test';
$con = mysql_connect($db_host, $db_user, $db_password) or die(mysql_error());
mysql_select_db($db_name, $con) or die(mysql_error());
mysql_query('set names utf8') or die(mysql_error());
?>

PHP學習
function likecate($path='') {
  // concat() 連接字段
  $sql = "select id,catename,path, concat(path,',',id) as fullpath from tp_likecate order by fullpath asc";
  $res = mysql_query($sql);
  $result = array();
  while($row=mysql_fetch_assoc($res)) {
    $deep = count(explode(',', trim($row['fullpath'], ','))); // explode字符串轉換為數組 implode數組轉換為字符串
    $row['catename'] = @str_repeat('??', $deep).'|--'.$row['catename'];
    $result[] = $row;
  }
  return $result;
}

PHP學習
// 簡單輸出
$res = likecate();
echo "<select name='cate'>";
foreach($res as $key=>$val) {
  echo "<option>{$val['catename']}</option>";
}
echo "</select>";
echo "<br />";
// 封裝辦法
function getPathCate($cateid) {
  $sql = "select *,concat(path, ',',id) fullpath from tp_likecate where id = $cateid";
  $res = mysql_query($sql);
  $row = mysql_fetch_assoc($res);
  $ids = $row['fullpath'];
  $sql = "select * from tp_likecate where id in($ids) order by id asc";
  $res = mysql_query($sql);
  $result = array();
  while($row = mysql_fetch_assoc($res)) {
    $result[] = $row;
  }
  return $result;
}
// 加上了鏈接的參數
function displayCatePath($cateid,$link='cate.php?cid=') { // 也可以組裝
  $res = getPathCate($cateid);
  $str = '';
  foreach($res as $k=>$v) {
    $str.= "<a href='{$link}{$v['id']}'>{$v['catename']}</a> > ";
  }
  return $str;
}
echo displayCatePath(4);