根据网址城市值更新<option>标记'selected'属性

Question

This is my URL: www.xyz.com/index?city=NY I am trying to update < option > tag's 'selected' attribute according to url's city value. This is my partial html:

 <script>
    function loadCity(val)
    {
      window.location.assign("/do/index?city="+val); //script that reload's page as per selected city value.

    }
   $(document).ready ( function(){
        var cityValue= <?=$_GET['city'] ?>;        
        var k = getElementById(cityValue);         
        k.option.setAttribute('selected', true);   
    });​                                            //this function not working
 </script>




<select id="city" onchange="loadCity(this.value)">
                    <option>Cities</option>
                        <?php $cities=get_cities(); ?>   //get cities from an array
                        <?php foreach($cities as $city): ?>

                        <option id="<?= $city?>" value="<?= $city?>"><?= $city?></option>  

                        <?php endforeach; ?>  
                    </select>

Tried a bunch of other stuff, nothing seams to work. Thanks in advance.(your response is greatly appreciated!)

Answer 1

Why are you setting the selected value in JavaScript? You could get rid of the entire document.ready part and do it in PHP.

<select id="city" onchange="loadCity(this.value)">
    <option>Cities</option>
    <?php $cities=get_cities(); ?>   //get cities from an array
    <?php foreach($cities as $city): ?>
         <option id="<?= $city; ?>" value="<?= $city; ?>" <?= $city == $_GET['city'] ? 'selected' : '' ?> ><?= $city; ?></option>  
    <?php endforeach; ?>  
</select>

Or in jQuery you could do

$("#city").val(cityValue);