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JavaScript

Posted by Eric Ewers
Eric Ewers
13,976 Points

Add sum of select box values with same ID using jQuery

I found a partial solution, but I need to add an id of "product" to all of these select boxes, then get the sum of only the selects with id="product". That way, if I have other select boxes in my form, they won't get targeted.

$("select").change(function() {
    var combined = 0;
    $("select").each(function() {
        combined += parseInt(this.value);
    });
    $("#sum").html(combined);
}).trigger("change");

<select>
      <option value=1>1</option>
      <option value=15>15</option>
</select>

<select>
      <option value=1>1</option>
      <option value=25>25</option>
    </select>

<select>
      <option value=1>1</option>
      <option value=2>2</option>
    </select>

    <p>
    Sum :<span id="sum">0</span>
    </p>

When I try the following, it only targets the first select, but not the rest.

$("#product").change(function() {
    var combined = 0;
    $("#product").each(function() {
        combined += parseInt(this.value);
    });
    $("#sum").html(combined);
}).trigger("change");

1 Answer

Hugo Paz
Hugo Paz
15,622 Points

Hi Eric,

Your issue is pretty simple, you are using IDs. IDs are supposed to be unique, only one per page if you will.

Change it from an ID to a Class and your code works perfectly.

Eric Ewers
Eric Ewers
13,976 Points

Wow...that is what happens when you stare at the screen too long. Thanks!