三级联动

 // JavaScript Document $(document).ready(function(e) { //找到ID=SANJI的DIV，造三个下拉扔进去 $("#sanji").html(""); //加载省的数据 LoadSheng(); //加载市的数据 LoadShi(); //加载区的数据 LoadQu(); //给省的下拉加点击事件 $("#sheng").click(function(){ //重新加载市 LoadShi(); //重新加载区 LoadQu(); }) //给市的下拉加点击事件 $("#shi").click(function(){ //重新加载区 LoadQu(); }) }); //加载省份的方法 function LoadSheng() { //省的父级代号 var pcode = "0001"; $.ajax({ async:false, url:"chuli.php", data:{pcode:pcode}, type:"POST", dataType:"TEXT", success: function(data){ var hang = data.trim().split("|"); var str = ""; for(var i=0;i"+lie[1]+""; } $("#sheng").html(str); } }); } //加载市的方法 function LoadShi() { //找市的父级代号 var pcode = $("#sheng").val(); $.ajax({ async:false, url:"chuli.php", data:{pcode:pcode}, type:"POST", dataType:"TEXT", success: function(data){ var hang = data.trim().split("|"); var str = ""; for(var i=0;i"+lie[1]+""; } $("#shi").html(str); } }); } //加载区的方法 function LoadQu() { //找区的父级代号 var pcode = $("#shi").val(); $.ajax({ url:"chuli.php", data:{pcode:pcode}, type:"POST", dataType:"TEXT", success: function(data){ var hang = data.trim().split("|"); var str = ""; for(var i=0;i"+lie[1]+""; } $("#qu").html(str); } }); } 

 <?php //给一个父级代号，返回该父级代号下所有的子地区 require "DBDA.class.php"; $db=new DBDA(); $pcode=$_POST["pcode"]; $sql="select areacode,areaname from chinastates where parentareacode='{$pcode}'"; echo $db->StrQuery($sql); 

 <?php class DBDA { public $host = "localhost"; public $uid = "root"; public $pwd = "123"; public $dbname = "test_123"; //执行SQL语句返回相应的结果 //$sql 要执行的SQL语句 //$type 代表SQL语句的类型，0代表增删改，1代表查询 function query($sql,$type=0) { $db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname); $result = $db->query($sql); if($type) { //如果是查询，显示数据 return $result->fetch_all(); } else { //如果是增删改，返回true或者false return $result; } } //返回字符串的方法 public function strquery($sql,$type=1) { $db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname); $result = $db->query($sql); $arr = $result->fetch_all(); $str=""; foreach($arr as $v) { $str = $str.implode("^",$v)."|"; } $str = substr($str,0,strlen($str)-1); return $str; } //返回JSON function JSONQuery($sql,$type=1) { $db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname); $r = $db->query($sql); if($type==1) { return json_encode($r->fetch_all(MYSQLI_ASSOC)); } else { return $r; } } }