Yii2.0 三级联动实现方法

view中代码

<?php
use yii\bootstrap\ActiveForm;

/* @var $this yii\web\View */
/* @var $form yii\bootstrap\ActiveForm */
?>

<?php $form = ActiveForm::begin(['enableClientValidation' => false]);?>

<?= $form->field($model,'province')->dropDownList($model->getCityList(0),
    [
        'prompt'=>'--请选择省--',
        'onchange'=>'
            $(".form-group.field-member-area").hide();
            $.post("'.yii::$app->urlManager->createUrl('member/site').'?typeid=1&pid="+$(this).val(),function(data){
                $("select#member-city").html(data);
            });',
    ]) ?>

<?= $form->field($model, 'city')->dropDownList($model->getCityList($model->province),
    [
        'prompt'=>'--请选择市--',
        'onchange'=>'
            $(".form-group.field-member-area").show();
            $.post("'.yii::$app->urlManager->createUrl('member/site').'?typeid=2&pid="+$(this).val(),function(data){
                $("select#member-area").html(data);
            });',
    ]) ?>
<?= $form->field($model, 'area')->dropDownList($model->getCityList($model->city),['prompt'=>'--请选择区--',]) ?>
<?php ActiveForm::end();?>

model中添加下面的函数

    /**
     * @param $pid
     * @return array
     */
    public function getCityList($pid)
    {
        $model = City::findAll(array('pid'=>$pid));
        return ArrayHelper::map($model, 'id', 'name');
    }

控制器中添加下面的代码：

    /**
     * Function output the site that you selected.
     * @param int $pid
     * @param int $typeid
     */
    public function actionSite($pid, $typeid = 0)
    {
        $model = new Member();
        $model = $model->getCityList($pid);

        if($typeid == 1){$aa="--请选择市--";}else if($typeid == 2 && $model){$aa="--请选择区--";}

        echo Html::tag('option',$aa, ['value'=>'empty']) ;

        foreach($model as $value=>$name)
        {
            echo Html::tag('option',Html::encode($name),array('value'=>$value));
        }
    }

City数据库结构：

/*
Navicat MySQL Data Transfer

Source Server         : MySQL
Source Server Version : 50624
Source Host           : localhost:3306
Source Database       : yii2advanced

Target Server Type    : MYSQL
Target Server Version : 50624
File Encoding         : 65001

Date: 2015-07-13 14:27:12
*/

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for yii2_city
-- ----------------------------
DROP TABLE IF EXISTS `yii2_city`;
CREATE TABLE `yii2_city` (
  `id` smallint(5) unsigned NOT NULL AUTO_INCREMENT,
  `pid` smallint(5) unsigned NOT NULL DEFAULT '0',
  `name` varchar(120) NOT NULL DEFAULT '',
  PRIMARY KEY (`id`),
  KEY `parent_id` (`pid`)
) ENGINE=MyISAM AUTO_INCREMENT=3410 DEFAULT CHARSET=utf8;