How to Avoid the Need For Ctrl-Click in a Multi-Select Box Using JavaScript

How to avoid the need for ctrl-click in a multi-select box using Javascript?

Check this fiddle: http://jsfiddle.net/xQqbR/1022/

You basically need to override the mousedown event for each <option> and toggle the selected property there.

$('option').mousedown(function(e) {
    e.preventDefault();
    $(this).prop('selected', !$(this).prop('selected'));
    return false;
});

For simplicity, I've given 'option' as the selector above. You can fine tune it to match <option>s under specific <select> element(s). For ex: $('#mymultiselect option')

Selecting multiple from an html select element without using ctrl key

You can save the Element.scrollTop and set it at the end.

$("select").mousedown(function(e){
    e.preventDefault();

    var select = this;
    var scroll = select .scrollTop;

    e.target.selected = !e.target.selected;

    setTimeout(function(){select.scrollTop = scroll;}, 0);

    $(select ).focus();
}).mousemove(function(e){e.preventDefault()});

http://jsfiddle.net/UziTech/cjjg68dr/114/

multi-select box without ctrl-click

The below code works in firefox 31.0,IE 10 and crome 36.0.1985.143. But it dose not work well if CTRL keys is used also.

 $('select').bind("click", function (event, target) {

        event.preventDefault();
        var CurrentIndex = event.target.selectedIndex==undefined? $(event.target).index(): event.target.selectedIndex
        var CurrentOption = $("option:eq(" + CurrentIndex+ ")", $(this));
        if ($(CurrentOption).attr('data-selected') == undefined || $(CurrentOption).attr('data-selected') == 'false') {
            $(CurrentOption).attr('data-selected', true);
        }
        else {
            $(CurrentOption).prop('selected', false).attr('data-selected', false);
        }

        $("option", $(this)).not(CurrentOption).each(function (Index, OtherOption) {
            $(OtherOption).prop('selected', ($(OtherOption).attr('data-selected') == 'true') ? true : false);
        });
         return false;
    });

html Select multiple option with simple click without pressing CTRL button

I think you want somethings like this :

$('select[multiple]').multiselect()

<!DOCTYPE html><html><head><link href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" /><link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-multiselect/0.9.15/css/bootstrap-multiselect.css" />
</head><body>
<select multiple="multiple">    <option value="cheese">Cheese</option>    <option value="tomatoes">Tomatoes</option>    <option value="mozarella">Mozzarella</option>    <option value="mushrooms">Mushrooms</option>    <option value="pepperoni">Pepperoni</option>    <option value="onions">Onions</option></select>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.7/js/bootstrap.js"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-multiselect/0.9.15/js/bootstrap-multiselect.min.js"></script></body></html>