Search numeric and text in DataTables JS

Question

I'm trying to improve DataTables search functionality based on this example . It makes the table footer searchable (as a string). I'd like to be able turn string filtering into numeric filtering by prefixing the search input with < or > sign.

I'm not good at JS. If there's a quick win here that would be much appreciated.

            <script>
                $(document).ready(function() {
                    $('#{{ v.table_id }} tfoot th').each( function () {
                        var title = $(this).text();
                        $(this).html( '<input type="text" placeholder="Search '+title+'" />' );
                    } );

                    var table = $('#{{ v.table_id }}').DataTable(
                    {
                        dom: 'Blfrtip',
                        buttons: ['copy'],
                        search: {"caseInsensitive": true},
                        "lengthMenu": [ [12, 24, 48, -1], [12, 24, 48, "All"] ]
                    } 
                );
                    table.columns().every( function () {
                        var that = this;

                        $( 'input', this.footer() ).on( 'keyup change', function () {
                            let re_gt = /^>/
                            let re_lt = /^</
                            var gt = re_gt.test(this.value)
                            var lt = re_lt.test(this.value)

/* NEED HELP WITH THIS PART */
                            if ( re_gt.test(this.value) ) {
                                var min = parseInt( this.value.slice(1), 10 )
                                that
                                    .filter( function ( value, index ) { return value < min ? false : true; } )
                                    .draw();
                            }

                            else if ( re_lt.test(this.value) ) {
                                var max = parseInt( this.value.slice(1), 10 )
                            }

/* THIS PART WORKS */
                            else {
                                if ( that.search() !== this.value ) {
                                    that
                                        .search( this.value )
                                        .draw();
                                }
                            }
                        } );
                    } );
                } );
            </script>

Answer 1

This seems awkward but it works. It would be cool if I were able to apply two active filters at the same time. Right now, if doing greater/less than filtering on two columns, switching to a second column resets the filter for the first column.

            <script>
                $(document).ready(function() {
                    $('#{{ v.table_id }} tfoot th').each( function () {
                        var title = $(this).text();
                        $(this).html( '<input type="text" placeholder="Search '+title+'" />' );
                    } );

                var table = $('#{{ v.table_id }}').DataTable(
                    {
                        dom: 'Blfrtip',
                        buttons: ['copy'],
                        order: [[ {{v.sort_col}} ]],
                        search: {"caseInsensitive": true},
                        "lengthMenu": [ [12, 24, 48, -1], [12, 24, 48, "All"] ]
                    } 
                );
                    table.columns().every( function () {
                        var that = this

                        $( 'input', this.footer() ).on( 'keyup change', function () {
                            var colnumber = that[0][0] /* got that by inspecting Object.entries(that) in dev mode */
                            let gtlt = /^[<>]/
                            if ( gtlt.test(this.value) ) {
                                var sign = this.value.slice(0,1)
                                var min = ( sign === '>' ? parseInt( this.value.slice(1), 10 ) || -Infinity : -Infinity )
                                var max = ( sign === '<' ? parseInt( this.value.slice(1), 10 ) ||  Infinity :  Infinity )
                                /* console.log(sign, min, max) */
                                $.fn.dataTable.ext.search.push(
                                    function(settings, data, dataIndex) {
                                        var values = parseFloat( data[colnumber] ) || 0
                                        /* console.log(min, max, values) */
                                        if (min == null && max == null) {
                                            return true;
                                        }
                                        if (values >= min && values <= max) {
                                            return true;
                                        }
                                        return false;
                                        }
                                    );
                                table.draw()
                                /* reset min/max filters to default, inactive values */
                                min = -Infinity
                                max =  Infinity
                            }

                            else {
                                if ( that.search() !== this.value ) {
                                    that
                                        .search( this.value )
                                        .draw();
                                }
                            }
                        } );
                    } );
                } );
            </script>