//第一种：遍历两种数据，找到相对应的元素

let me = this
for (var j = 0; j < repeat_items.length; j++) {    //后台返回来的选项
	 for (var i = 0; i < me.list.length; i++) {    

			var pId = repeat_items[j];
			var Id = me.list[i].id
			if (pId == Id) {    //找到相对应的元素
			    me.list[i].checked = true
				console.log("找到你了")
				continue;
				}
		}
}

//第二种
for(var a in me.userRole){
    if(me.userRole[a].son == undefined){ 
        for(var b in me.userRole[a].son ){
               console.log(me.userRole[a].son[b].son_menu_name);
           }
            return false;
         }else{
                for(var b in me.userRole[a].son ){
                    var idss  = me.userRole[a].son[b].id;    //遍历出找到ID
                    if(menu_son.includes(idss) == true){    //判断该数组里是否含有该字符串
                       me.userRole[a].son[b].checked = true    //回显成功
                       }
                   }
               }
    }

效果图