将Multiselect下拉选项分配给Javascript中的字符串变量

Question

I would like to store a couple of options from a HTML multiselect Drop-down function to another variable in Javascript.

<form name="myedit" id="myedit" action="next.php" method="post" onsubmit="return copyLongDesc( 'oxarticles__oxlongdesc' );"
   <select id="Project" name="Data" size="10" multiple="multiple" onchange="rewrite_data();">
        <option value="1">1</option>
        <option value="2">2</option>
        <option value="3">3</option>
        <option value="4">4</option>
        <option value="5">5</option>
    </select>
</form>

It has to be stored in this string variable 'editval[oxarticles__oxmerkmaleaa]' with any change Event. The variable is already in the formular from this script.

I need to know how I get that to work ?

I would appreciate your help.

Answer 1

We create an event listener change and pass a function to it. See it in action, working example.

 var select = document.getElementById('Project'); function selectedOptions() { var result = []; var options = this.options; for (i = 0; i < options.length; i++) { var option = options[i]; if (option.selected) { result.push(option.value); } } console.log(result); return result; } select.addEventListener('change', selectedOptions); 

 <select id="Project" name="Data" size="10" multiple="multiple" > <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select>