【ajax+php】动态展示4级单位（省、市、县、镇）

1、本篇教程以ajax+php动态展示【省、市、县、镇】四级地区单位

2、效果图：     

3、不废话，贴代码！

HTML：

          <div class="form-group">
            <label class="col-sm-3 control-label" for="onecity"> 
                地区分类
                <span class="text-danger">*</span>
            </label>
            <div class="col-sm-2">
                <select class="form-control"  id="onecity" name="onecity" onchange="city()">
                    <option value="">请选择一级地区</option>
                    {loop $one $v}
                    <option value="{$v['id']}">{$v['name']}</option>
                    {/loop}
                </select>
            </div>
            <!-- 二级城市 -->
            <div class="col-sm-2" id="ss">
            </div>
            <!-- 三级城市 -->
            <div class="col-sm-2" id="ss2">
            </div>
            <div class="col-sm-2" id="ss3">
                    </div>
            <script text="text/javascript">
                        function city(){
                             var one=$("#onecity").val();
                             $.ajax({
                                   type: "POST",
                                   url: "/index.php?do=pubh***_third&id=19&step=step1_third&fc=1&one="+one,
                                   success: function(msg){
                                       $("#ss").empty();
                                       $("#ss").append(msg);
                                   }
                                });    
                        }
                    </script>
                    <script text="text/javascript">
                        function city2(){
                             var two=$("#twocity").val();
                             $.ajax({
                                   type: "POST",
                                   url: "/index.php?do=pubh***_third&id=19&step=step1_third&fc=2&two="+two,
                                   success: function(msg){
                                       $("#ss2").empty();
                                       $("#ss2").append(msg);
                                   }
                                });    
                        }
                    </script>
                    <script text="text/javascript">
                function city3(){
                     var three=$("#threecity").val();
                     $.ajax({
                           type: "POST",
                           dataType: 'json',
                           url: "/index.php?do=pubh***_third&id=19&step=step1_third&fc=3&three="+three,
                           success: function(res){
                                   $("#ss3").empty();
                             if(res.data!='error'){
                                   $("#ss3").append(res.data);
                             }
                           }
                        });    
                }
            </script>
        </div>

php：

        //1、首先将省级单位给输出到页面 -- 1225
        $one=db_factory::get_table_data("*",'w***_district','upid=0');
        
        //2、ajax动态判断传过来的pid（省），获取市级单位，并动态输出<select><option>数据html
        if($_R[fc]==1){
            if($_R['one']){
                $msg=db_factory::get_table_data("*","w***_district","upid=".$_R['one']);
            }
            $dis='<select class="form-control" name="twocity"  id="twocity" onchange="city2();choose_village();"><option value="">请选择二级地区</option>';
            foreach($msg as $v){
                $dis.='<option  value="'.$v[id].'">'.$v[name].'</option>';
            }
            $dis.='</select>';
            echo $dis;
            die;
        }
        if($_R[fc]==2){
            if($_R['two']){
                $msg=db_factory::get_table_data("*","w***_district","upid=".$_R['two']);
            }
            $dis='<select class="form-control" name="threecity" id="threecity" onchange="city3();"><option value="">请选择三级地区</option>';
            foreach($msg as $v){
                $dis.='<option value="'.$v[id].'">'.$v[name].'</option>';
            }
            $dis.='</select>';
            echo $dis;
            die;
        }
        if($_R[fc]==3){
            if($_R['three']){
                $msg=db_factory::get_table_data("*","wi***_district","upid=".$_R['three']);
            }
            /* 四级单位有可能没有的，比如直辖市、自治州 */
            if($msg){
                $dis='<select class="form-control" name="fourcity"  id="fourcity" ><option value="">请选择四级地区</option>';
                foreach($msg as $v){
                    $dis.='<option value="'.$v[id].'">'.$v[name].'</option>';
                }
                $dis.='</select>';
                kekezu::echojson("",1,$dis);
                //echo $dis;
                die;
            }
            else{
                kekezu::echojson("",2,'error');//参数依次msg、status、data
                die ();
            }
        }

到这里就结束了，很简答的一个ajax应用。