HTML5/Javascript datatables order/sort of columns

had a similar challenge with Data Tables a while ago. And this was with dates, formatted numbers and also with special characters in German. Your name sounds like you are from Scandinavia; might be relevant for you too I guess ...

You would need the following data tables plug ins to do all of this:

This one is for date time sorting: https://datatables.net/plug-ins/sorting/datetime-moment It also requires moment.js which I strongly recommend. https://momentjs.com/

This one is for international sorting when using special characters such as ä, ö ü etc. https://datatables.net/plug-ins/sorting/intl

And this one is for formatted number sorting: https://datatables.net/plug-ins/sorting/formatted-numbers

The examples below are about auto-detection of the respective fields depending on the user language.

Implementation examples:

So this is about formatted numbers. English format would be 1,000,000.99. German format is 1.000.000,99. It also takes care of empty fields.

//sorting of formatted numbers in English and German format
$.extend( $.fn.dataTable.ext.type.order, { 
    "formatted-num-pre": function ( a ) {
        if (lang == 'de') {
            a = a.toString().replace( /[\.]/g, "" );
            a = a.toString().replace( /[\,]/g, "." );
        } else {
            a = a.toString().replace( /[\,]/g, "" );
        }
        a = a.toString().replace( /[^\d.-]/g, "" );
        a = parseFloat(a);
        if ( ! isNaN(a) ) {
            return a;
        } else {
//14 digit negative number to make sure empty cells always stay at the bottom / top
            return -99999999999999;
        }
    },
    "formatted-num-asc": function ( a, b ) {
            return a - b;
    },
    "formatted-num-desc": function ( a, b ) {
            return b - a;
    }
} );

This is about international sorting:

//sorting:
//Use the phonebook variant of the German sort order, 
//which expands umlauted vowels to character pairs: ä → ae, ö → oe, ü → ue.
if (lang === 'de') {
    $.fn.dataTable.ext.order.intl("de-DE-u-co-phonebk");
} else {
    $.fn.dataTable.ext.order.intl("en-GB");
}

And finally this is about date sorting:

//should be positioned after the number formatting to make sure
//date columns don't accidentally are assigned formatted-num
//set parms for date sorting using moment.js
$.fn.dataTable.moment( 'L', momentLocale );

the variable momentLocale in my example is either 'de' or 'en-gb'. The respective date formats are 10.11.2018 (German) or 10/11/2018 (English UK). (As opposed to 11/10/2018 in the American format which I think requires momentLocale to be 'en').