js select实现省市区联动选择

var $ = require('jquery'),
 $window = $(window),
 data = require('./data-new'),
 $doc = $(document);

var __DEFAULTS__ = {
 wrap:'',
 itemName: ['省', '市', '区/县'],
 items: ['province', 'city', 'area'],
 callback: function(field, index) {} // 点击切换得时候才会执行

};


 function Area(options){
  options = $.extend({}, __DEFAULTS__, options);
  var that = this;
  that.wrapper = $(options.wrap);
  that.selectArr = that.wrapper.data('default')?that.wrapper.data('default').split(','):[110000,110100,110101]; //
  that.items = options.items;
  that.itemName = options.itemName;
  that.callback = options.callback;
  that.setValue();
  that.events();
  that.default = that.wrapper.data('default'); //默认输出省市区的id
  that.validinput = $("#default-area");
  var validval = that.default!==undefined?that.default:'';
  that.validinput.val(validval);

 }

Area.prototype = {
 constructor: Area,
 //创建select，输出相应的数据
 createItems:function(itemname,data,selectId){
  var that = this;
  //如果默认的defalut值没输出，则默认的给select添加相应的填写提示
  var html = '<select name="'+itemname+'">'+(that.default === undefined ?'<option value="'+itemname+'" selected ="selected">'+that.itemName[that.index]+'</option> ' : '');

  for (var k in data) {

   html += '<option value ="'+ data[k].id +'"'+(selectId === data[k].id ? 'selected = "selected"' : '')+'>' + data[k].name + '</option>';

  }
  html += '</select>'; 
  return html;
 },
 //设置初始值
 setValue:function(){
  var that = this,
   html = '';

  $.each(that.selectArr,function(index,k){
   that.index = index;
    html += that.createItems(that.items[index],that.getData(that.items[index],that.selectArr[index-1]),k);

  })
  that.wrapper.append(html)

 },
 //获取数据
 getData: function(type, pid) {

  if (type === 'province') {
   return data.provinces || []; // 省份信息不需要pid
  }

  if (type === 'city') {
   return data.cities[pid] || [];
  }

  if (type === 'area') {
   return data.areas[pid] || [];
  }
 },
  //获取select索引值
 getItemIndex:function(type){
  var that = this;
  for(var i= 0,l = that.items.length;i<l;i++){
   if(that.items[i] == type){
    return i;
   }
  }

 },
 //触发change时候，select下一位值重新初始化
 setItemVal:function(select){

  var that = this;
  var $this = select,
   previd = $this.val(),
   $type =$this.attr('name'),
   $nxtType = '';

  if($type!='area'){

   $nxtType = that.items[that.getItemIndex($type)+1];

   var data = that.getData($nxtType,previd),
    html = that.createItems($nxtType,data,previd),
    nextSelect = $('select[name="'+$nxtType+'"]');

   if($this.siblings('select[name="'+$nxtType+'"]').length>0){
    nextSelect.remove();
   }
   $this.after(html);
   nextSelect.find('option:first').prop('selected',true);
   $('select[name="'+$nxtType+'"]').trigger('change');
  } else{

   that.validinput.val($this.val()).trigger('validate')
  }
  that.index = that.getItemIndex($type);
  //触发change后可以设置回调函数
  if (that.callback) {
   that.callback.call(this, select, that.getItemIndex($type));
  }

 },
 events:function(){
  var that = this;
  //select change事件
  $doc.on('change','.area-container select',function(){
   that.setItemVal($(this));

  })
 }
}

module.exports = Area;