Question

When the first dropdown is selected, I’m trying to dynamically update the options in the second dropdown. It’s working fine in FF, Chrome etc but doesn’t work in IE 8/9 and I don’t understand why. Here’s a jsFiddle

<div class="custom-field">            
    <label for="dropdown1">Select country:</label>
    <select id="dropdown1" name='properties[country]'>
        <option value="USA">USA</option>
        <option value="JAPAN">JAPAN</option>
    </select>
</div>
<div class="custom-field">            
    <label for="dropdown2">Select font:</label>
    <select id="dropdown2" name='properties[font]'>
        <option class="us" value="font1">Font1</option>
        <option class="us" value="font2">Font2</option>
        <option class="us" value="font3">Font3</option>
        <option class="jp" value="font4">Font4</option>
        <option class="jp" value="font5">Font5</option>
        <option class="jp" value="font6">Font6</option>              
    </select>
</div>  



function showFont(fontOpt){
    if (jQuery('#dropdown1').val() === 'USA'){
        var showOptions = fontOpt.filter('.us');
    } else {    
        var showOptions = fontOpt.filter('.jp');
    }
    jQuery('#dropdown2').html(showOptions);
    jQuery('#dropdown2').prop('selectedIndex', 0);
}


$(document).ready(function() {
    // get the child elements of font dropdown
    var fontOptions = $("#dropdown2").children('option');    
    $("#dropdown2").html('');

    showFont(fontOptions);

    $('#dropdown1').on("change", function(e){
        showFont(fontOptions);
    });    

});

Answer 1

$("#dropdown2").html('');

problem is with this line. Remove this line and your code will work fine.

Instead of this you may use

$("#dropdown2").children('option').remove();