PHP 实现无限极栏目分类

首先，创建一个DB

CREATE TABLE IF NOT EXISTS `class` (
  `id` mediumint(6) NOT NULL AUTO_INCREMENT,
  `title` varchar(30) NOT NULL,
  `pid` mediumint(6) NOT NULL DEFAULT ‘0‘,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8

然后插入数据

INSERT INTO `class` VALUES (1, ‘品牌女装‘, 0);
INSERT INTO `class` VALUES (2, ‘精品男装‘, 0);
INSERT INTO `class` VALUES (3, ‘连衣裙‘, 1);
INSERT INTO `class` VALUES (4, ‘旗袍‘, 1);
INSERT INTO `class` VALUES (5, ‘燕尾服‘, 2);

数据的结构能够自己去设计

这里采用递归的方法去实现无限极栏目分类

<?php 

$con = mysql_connect("localhost","root","123456");

mysql_query("set names ‘utf8‘");
mysql_select_db("test");

function get_str($id = 0) {
    global $str;
    $sql = "select id,title from class where pid= $id";
    $result = mysql_query($sql);
    if($result && mysql_affected_rows()){
        $str .= ‘<ul>‘;
        while ($row = mysql_fetch_array($result)) {
            $str .= "<li>" . $row[‘id‘] . "--" . $row[‘title‘] . "</li>";
            get_str($row[‘id‘]);
        }
        $str .= ‘</ul>‘;
    }
    return $str;
} 

echo get_str(0); 

?>

返回一个数组

<?php 

$con = mysql_connect("localhost","root","123456");

mysql_query("set names ‘utf8‘");
mysql_select_db("test");

function get_array($id=0){
    $sql = "select id,title from class where pid= $id";
    $result = mysql_query($sql);
    $arr = array();
    if($result && mysql_affected_rows()){
        while($rows=mysql_fetch_assoc($result)){
            $rows[‘list‘] = get_array($rows[‘id‘]);
            $arr[] = $rows;
        }
        return $arr;
    }
}
$list = get_array(0);
var_dump($list);?>