Ajax+jQuery实现省市区三级联动功能

<?php $pcode = $_POST["pcode"]; require_once "./DBDA.class.php"; $db = new DBDA(); $sql = "select * from chinastates where parentareacode='{$pcode}'"; echo $db->JsonQuery($sql,0); 封装类 <?php class DBDA{ public $host="localhost"; public $uid="root"; public $pwd=""; public $dbname="0710_info"; /* query方法:执行用户给的sql语句,并返回相应的结果 $sql:用户需要执行的sql语句 $type:用户需要执行的sql语句的类型 return:如果是增删语句改返回true或false,如果是查询语句返回二维数组 */ public function query($sql,$type=1){//默认true为增删改 $db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname); if(mysqli_connect_error()){ return "连接失败!"; } $result = $db->query($sql); if($type==1){ return $result;//增删改语句返回true或false }else{ return $result->fetch_all();//查询语句返回二维数组 } } //此方法用于ajax中用于对取出的数据（二维数组）进行拼接字符串处理 public function StrQuery($sql,$type=1){ $db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname); if(mysqli_connect_error()){ return "连接失败!"; } $result = $db->query($sql); if($type==1){ return $result;//增删改语句返回true或false }else{ $arr = $result->fetch_all();//查询语句返回二维数组 $str = ""; foreach($arr as $v){ $str = $str.implode("^", $v)."|"; } $str = substr($str, 0,strlen($str)-1); return $str; } } //此方法用于ajax中用于返回为json数据类型时使用 public function JsonQuery($sql,$type=1){ $db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname); if(mysqli_connect_error()){ return "连接失败!"; } $result = $db->query($sql); if($type==1){ return $result;//增删改语句返回true或false }else{ $arr = $result->fetch_all();//查询语句返回二维(关联)数组 return json_encode($arr);//将数组转换成json } } }