记录：fastadmin搜索栏实现某字段动态下拉搜索
方式一：使用selectpicker组件，可多选

{
    
     field: 'travel_agency', title:__('Travel_agency'),addClass:"selectpicker", operate:"IN",data:"multiple", searchList: $.getJSON("travel/bill/travel_agencylist_pay")},

方式二：使用selectpage组件，可多选，可搜索

columns: [[
	        {
    
    field: 'travel_agency', title: __('Travel_agency'), operate:"IN"},
	     ]],
	  onPostCommonSearch: function (event, table) {
    
    
	      //动态下拉列表
	      $("form.form-commonsearch input[name='travel_agency']")
	      .addClass("selectpage")
	      .data("multiple","true")
	      .data("source", "travel/bill/travel_agencylist_pay");
	      //.val();	设置默认值
	  },