carry some extra information in an HTML select/option dropdown list

Question

I want to carry some extra hidden information (eg: postal code) in an HTML select/option dropdown list and make it available to a javascript function when user changes option box selection.

This is the type of thing I would like to do (but it does not work).

<select id="sel_activity" onchange="selectionChange(this.info)"> 
    <option info=""       value="CAR">CAR PROBLEM</option> 
    <option info=""       value="COFFEE">Coffee Break</option>
    <option info="45678"  value="INV">INVENTORY COUNT</option>
    <option info="23567"  value="INVDROP">Inventory</option>
    <option info="" value="LUNCH">Lunch Break</option> 
    <option info="87654"  value="MEET">Meeting</option>
</select>

.
.
.

function selectionChange(info){      
    alert(info);
}

Answer 1

HTML 5 provides data-* attributes, you can define your own attributes just prefix them with data-. Like data-info, data-zip or whatever.