<select v-model="citys" name="cityVal" @change="schoolName(citys)">
<option v-for="(item,index) in city" :value="item.val" v-text="item.name" ></option>
</select>

<select v-model="schools" name="schoolVal">
<option v-for="(item,index) in school" :value="item.val" v-text="item.name" ></option>
</select>

<script>
    var vue = new Vue({
        el: ‘#body‘,
        data: function() {
            return {
                city: [{
                    val: ‘0‘,
                    name: ‘城市‘
                }],
                citys: 0,
                school: [{
                    val: ‘0‘,
                    name: 
 
‘高校‘
                }],
                schools: 0,
                schoolAjax:‘‘
            }
        },
        methods: {
            cityName: function() {
                var this_obj = this;
                $.ajax({
                    type: "post",
                    url: $app+"/Clan/city",
                    dataType: 
 
"json",
                    success: function(res) {
                        if(res.status) {
                            $.each(res.info,function(k, v) {
                                this_obj.city.push({
                                    name:v.ar_name,
                                    val:v.ar_id,
                                })
                            })
                            
                        } else {
                            
                        }
                    },
                    error: function() {
                        $.alert({
                            msg: ‘傳輸錯誤1‘
                        })
                    }
                });
            },
            schoolName: function(citys) {
                var this_obj = this;    
                var data = { ar_id:citys};                
                $.ajax({
                    type: "post",
                    data:data,
                    url: $app+"/Clan/school",
                    dataType: "json",
                    success: function(res) {
                        this_obj.school=[{ val: ‘0‘,name: ‘高校‘}]
                        if(res.status) {
                            $.each(res.info,function(k, v) {
                                this_obj.school.push({
                                    val:v.sc_id,
                                    name:v.sc_name
                                })
                            });
                                this_obj.schools=this_obj.schoolAjax;
                        } else {
                            
                    },
                    error: function() {
                        $.alert({
                            msg: ‘傳輸錯誤7‘
                        })
                    }
                });
            },
            defules:function(){
                var this_obj = this;
                $.ajax({
                    type: "post",
                    url: $app+"/Call/team_user",
                    dataType: "json",
                    success: function(res) {
                        console.log(res.info);
                        if(res.status) {
                                
                                this_obj.schoolName(res.info.us_arid);
                                this_obj.schoolAjax=res.info.us_scid;                    
                            
                        } else {

                        }
                    },
                    error: function() {
                        $.alert({
                            msg: ‘傳輸錯誤5‘
                        })
                    }
                });
            }
            }
    })    

    vue.cityName();   
    vue.defules();

vue.js用select實現省，市，提交後，默認顯示省，市信息