html - Use HTML5 (datalist) autocomplete with 'contains' approach, not just 'starts with'

Question

(I can't find it, but then again I don't really know how to search for it.)

I want to use <input list=xxx> and <datalist id=xxx> to get autocompletion, BUT I want the browser to match all options by 'contains' approach, instead of 'starts with', which seems to be standard. Is there a way?

If not simply, is there a way to force-show suggestions that I want to show, not those that the browser matched? Let's say I'm typing "foo" and I want to show options "bar" and "baz". Can I force those upon the user? If I just fill the datalist with those (with JS), the browser will still do its 'starts with' check, and filter them out.

I want ultimate control over HOW the datalist options show. NOT over its UI, flexibility, accessibility etc, so I don't want to completely remake it. Don't even suggest a jQuery plugin.

If I can ultimate-control form element validation, why not autocompletion, right?

edit: I see now that Firefox does use the 'contains' approach... That's not even a standard?? Any way to force this? Could I change Firefox's way?

edit: I made this to illustrate what I'd like: http://jsfiddle.net/rudiedirkx/r3jbfpxw/

• HTMLWG's specs on [list]
• W3's specs on datalist
• DavidWalsh example
• HONGKIAT's summary on behaviors..?

Answer 1

'contains' approach

Maybe this is what you are looking for (part 1 of your question).

It goes with the limitation of "starts with" and changes when a selection is made.

'use strict';
function updateList(that) {
    if (!that) {
        return;
    }
    var lastValue = that.lastValue,
        value = that.value,
        array = [],
        pos = value.indexOf('|'),
        start = that.selectionStart,
        end = that.selectionEnd,
        options;

    if (that.options) {
        options = that.options;
    } else {
        options = Object.keys(that.list.options).map(function (option) {
            return that.list.options[option].value;
        });
        that.options = options;
    }

    if (lastValue !== value) {
        that.list.innerHTML = options.filter(function (a) {
            return ~a.toLowerCase().indexOf(value.toLowerCase());
        }).map(function (a) {
            return '<option value="' + value + '|' + a + '">' + a + '</option>';
        }).join();
        updateInput(that);
        that.lastValue = value;
    }
}

function updateInput(that) {
    if (!that) {
        return;
    }
    var value = that.value,
        pos = value.indexOf('|'),
        start = that.selectionStart,
        end = that.selectionEnd;

    if (~pos) {
        value = value.slice(pos + 1);
    }
    that.value = value;
    that.setSelectionRange(start, end);
}

document.getElementsByTagName('input').browser.addEventListener('keyup', function (e) {
    updateList(this);
});
document.getElementsByTagName('input').browser.addEventListener('input', function (e) {
    updateInput(this);
});

<input list="browsers" name="browser" id="browser" onkeyup="updateList();" oninput="updateInput();">
<datalist id="browsers">
    <option value="Internet Explorer">
    <option value="Firefox">
    <option value="Chrome">
    <option value="Opera">
    <option value="Safari">
</datalist>