在JavaScript和PHP中的字符串中获取多个选定的复选框值

Question

我在数据库表中有位置名称和位置ID。使用foreach循环，我在PHP的复选框中打印值。我有一个触发JavaScript的提交按钮。我希望用户在javascript变量中选择所有用逗号分隔的复选框值。我怎样才能做到这一点？

    <!-- Javascript -->
<script>
        function getLoc(){
                var all_location_id = document.getElementByName("location[]").value;
                     var str = <!-- Here I want the selected checkbox values, eg: 1, 4, 6 -->

            }
        <script>

foreach($cityrows as $cityrow){
echo '<input type="checkbox" name="location[]" value="'.$cityrow['location_id'].'" />'.$cityrow['location'];
echo '<br>';
}
echo '<input name="searchDonor" type="button" class="button" value="Search Donor" onclick="getLoc()" />';

Answer 1

var checkboxes = document.getElementsByName('location[]');
var vals = "";
for (var i=0, n=checkboxes.length;i<n;i++) 
{
    if (checkboxes[i].checked) 
    {
        vals += ","+checkboxes[i].value;
    }
}
if (vals) vals = vals.substring(1);