javascript - 如何在更改时提交多个下拉菜单

Question

所以我在index.php上创建了四个下拉列表

<select name="filter_month" class="filters">
    <option>Select a Month</option>
    <option value="1">January</option>
    <option value="2">February</option>
    ....
</select>
<select name="filter_year" class="fitlers">
    <option>Select a Year</option>
    <option value="2015">2015</option>
    <option value="2016">2016</option>
</select> 
<select name="filter_category" class="filters">
    <option>Select a Category</option>
    <option value="1">Running</option>
    <option value="2">Trail Running</option>
</select>
<select name="filter_country" class="filters">
    <option>Select a Country</option>
    <option value="1">Canada</option>
    <option value="2">United States</option>
</select>

现在我不会做的是使用下拉列表中每个选定的值创建一个过滤器并将帖子发送到filters.php

$(function) {

   $('.filters').on('change', function(){
      // How send value from each Dropdown?
   });

} 

在filters.php上我创建了这段代码，如果我选择了这些选项中的任何一个($mm，$yy，$cat，$country)，如何返回数据

<?php 

if ($_SERVER['REQUEST_METHOD'] === 'POST') {

   $mm      = $_POST['filter_month'];
   $yy      = $_POST['filter_year'];
   $cat     = $_POST['filter_category'];
   $country = $_POST['filter_country'];

   // ... connection to database 
   $query = "how can filter by month, year, category and country";
   // ... Execute query
   // ... while ...
   echo $query; 
  // ... end while ...
}

谢谢!

Answer 1

您应该将选择放入 HTML 表单中(例如使用 id myForm 并使用 jQuery 发送它。

$(function) {
    $('.filters').on('change', function(){
        $('#myForm').submit();
    });
}