How to get all selected values of a multiple selec

Question

I have a <select> element with the multiple attribute. How can I get this element's selected values using JavaScript?

Here's what I'm trying:

function loopSelected() { 
    var txtSelectedValuesObj = document.getElementById('txtSelectedValues');
    var selectedArray = new Array();
    var selObj = document.getElementById('slct'); 
    var i;
    var count = 0;
    for (i=0; i<selObj.options.length; i++) { 
        if (selObj.options[i].selected) {
            selectedArray[count] = selObj.options[i].value;
            count++; 
        } 
    } 
    txtSelectedValuesObj.value = selectedArray;
}

Answer 1

You can use [].reduce for a more compact implementation of RobG's approach:

var getSelectedValues =  function(selectElement) {
  return [].reduce.call(selectElement.options, function(result, option) {
    if (option.selected) result.push(option.value);
    return result;
  }, []);
};

Answer 2

Riot js code

this.GetOpt=()=>{

let opt=this.refs.ni;

this.logger.debug("Options length "+opt.options.length);

for(let i=0;i<=opt.options.length;i++)
{
  if(opt.options[i].selected==true)
    this.logger.debug(opt.options[i].value);
}
};

//**ni** is a name of HTML select option element as follows
//**HTML code**
<select multiple ref="ni">
  <option value="">---Select---</option>
  <option value="Option1 ">Gaming</option>
  <option value="Option2">Photoshoot</option>
</select>

Answer 3

Check-it Out:

HTML:

<a id="aSelect" href="#">Select</a>
<br />
<asp:ListBox ID="lstSelect" runat="server"  SelectionMode="Multiple" Width="100px">
    <asp:ListItem Text="Raj" Value="1"></asp:ListItem>
    <asp:ListItem Text="Karan" Value="2"></asp:ListItem>
    <asp:ListItem Text="Riya" Value="3"></asp:ListItem>
    <asp:ListItem Text="Aman" Value="4"></asp:ListItem>
    <asp:ListItem Text="Tom" Value="5"></asp:ListItem>
</asp:ListBox>

JQUERY:

$("#aSelect").click(function(){
    var selectedValues = [];    
    $("#lstSelect :selected").each(function(){
        selectedValues.push($(this).val()); 
    });
    alert(selectedValues);
    return false;
});

CLICK HERE TO SEE THE DEMO

Answer 4

Building on Rick Viscomi's answer, try using the HTML Select Element's selectedOptions property:

let txtSelectedValuesObj = document.getElementById('txtSelectedValues');
[...txtSelectedValuesObj.selectedOptions].map(option => option.value);

In detail,

• selectedOptions returns a list of selected items.
• Specifically, it returns a read-only HTMLCollection containing HTMLOptionElements.
• ... is spread syntax. It expands the HTMLCollection's elements.
• [...] creates a mutable Array object from these elements, giving you an array of HTMLOptionElements.
• map() replaces each HTMLObjectElement in the array (here called option) with its value (option.value).

Dense, but it seems to work.

Watch out, selectedOptions isn't supported by IE!

Answer 5

ES6

[...select.options].filter(option => option.selected).map(option => option.value)

Where select is a reference to the <select> element.

To break it down:

• [...select.options] takes the Array-like list of options and destructures it so that we can use Array.prototype methods on it (Edit: also consider using Array.from())
• filter(...) reduces the options to only the ones that are selected
• map(...) converts the raw <option> elements into their respective values

Answer 6

My template helper looks like this:

 'submit #update': function(event) {
    event.preventDefault();
    var obj_opts = event.target.tags.selectedOptions; //returns HTMLCollection
    var array_opts = Object.values(obj_opts);  //convert to array
    var stray = array_opts.map((o)=> o.text ); //to filter your bits: text, value or selected
    //do stuff
}