Replacing empty date with string

bczm8703

would like to check if it is possible to replace the cell with an empty date with a string, eg: Never, and this string should not affect the sorting of the date. this string is to be sorted at last.

rf1234

It depends on what you are using.

If you are using columns.data
https://datatables.net/reference/option/columns.data
it is easy. Just use a renderer.

columns: [
    {   data: "yourDateField",
        render: function ( data, type, row ) {
            if ( data <= "" ) {
                return "Never";
            }
            return data;
        }    
    },

If you are not using columns data you need to work with cell().data().
https://datatables.net/reference/api/cell().data()

Sorting: Same thing, it depends on what you are using.

rf1234

Sorting using a modified version of this plugin: https://datatables.net/plug-ins/sorting/datetime-moment

Here is a modified version that sorts "Never" to the end (if DD.MM.YYYY is your date format; you would need to adjust this):

(function (factory) {
    if (typeof define === "function" && define.amd) {
        define(["jquery", "moment", "datatables.net"], factory);
    } else {
        factory(jQuery, moment);
    }
}(function ($, moment) {
 
$.fn.dataTable.moment = function ( format, locale ) {
    var types = $.fn.dataTable.ext.type;
 
    // Add type detection
    types.detect.unshift( function ( d ) {
        if ( d ) {
            // Strip HTML tags and newline characters if possible
            if ( d.replace ) {
                d = d.replace(/(<.*?>)|(\r?\n|\r)/g, '');
            }
 
            // Strip out surrounding white space
            d = $.trim( d );
        }
 
        // Null and empty values are acceptable
        if ( d === '' || d === null || d === "Never" ) {
            return 'moment-'+format;
        }
 
        return moment( d, format, locale, true ).isValid() ?
            'moment-'+format :
            null;
    } );
 
    // Add sorting method - use an integer for the sorting
    types.order[ 'moment-'+format+'-pre' ] = function ( d ) {
        if ( d ) {
            
            if ( d === "Never" ) {
                d = "31.12.2999";
            }
            // Strip HTML tags and newline characters if possible
            if ( d.replace ) {
                d = d.replace(/(<.*?>)|(\r?\n|\r)/g, '');
            }
 
            // Strip out surrounding white space
            d = $.trim( d );
        }
         
        return !moment(d, format, locale, true).isValid() ?
            Infinity :
            parseInt( moment( d, format, locale, true ).format( 'x' ), 10 );
    };
};
 
}));