thinkPHP+mysql+ajax实现的仿百度一下即时搜索效果详

<?php
namespace Wechat\Controller;
use Think\Controller;
/**
 * 学校模块控制层
 */
class SchoolController extends Controller {
  //学校选择页面
  public function index(){
    $County = D("County");
    $School = D("School");
    //获取所有的省份列表
    $cityList = $County->where("pid = 0")->order("sort desc")->select();
    //遍历省份数据，获取二级城市列表
    foreach ($cityList as $key => $value) {
      $countyList[] = $County->where("pid = ".$value['id'])->order("sort desc")->select();
    }
    //如果url传过来省级编号，就保存，否则就默认山东为要显示的省份
    if(!empty($_GET['cityid'])){
      $cityid = $_GET['cityid'];
    }else{
      //6号代码山东的城市编号
      $cityid = 6;
    }
    //查询此省份编号中的所有城市
    $countyList = $County->where("pid = ".$cityid)->order("sort desc")->select();
    //查询城市中的所有学校
    foreach ($countyList as $key => $value) {
      $countyList[$key]['school'] = $School->where("cid = ".$value['id'])->select();
    }
    //给视图层赋值
    $this->assign("cityList",$cityList);
    $this->assign("countyList",$countyList);
    //显示视图层
    $this->display();
  }
  //根据关键字进行查找
  public function get_school_by_key(){
    $key = $_POST['key'];//获取关键字
    if(empty($key))
      $this->ajaxReturn(array("flag"=>0,"data"=>array())); //如果关键字为空，就返回空数组
    //查询学校
    $School = D("School");
    $where['name'] = array("like","%".$key."%");
    $schoolList = $School->where($where)->limit("6")->select();
    if(empty($schoolList))
      $this->ajaxReturn(array("flag"=>0,"data"=>array()));//如果数据为空，也返回空数组
    $this->ajaxReturn(array("flag"=>1,"data"=>$schoolList));//返回学校列表
  }
}