合并相同的列

<script type="text/javascript">
            jQuery.fn.rowspan = function(colIdx) { //封装的一个JQuery小插件
                return this.each(function() {
                    var that;
                    $('tr', this).each(function(row) {
                        $('td:eq(' + colIdx + ')', this).filter(':visible').each(function(col) {
                            if(that != null && $(this).html() == $(that).html()) {
                                rowspan = $(that).attr("rowSpan");
                                if(rowspan == undefined) {
                                    $(that).attr("rowSpan", 1);
                                    rowspan = $(that).attr("rowSpan");
                                }
                                rowspan = Number(rowspan) + 1;
                                $(that).attr("rowSpan", rowspan);
                                $(this).hide();
                            } else {
                                that = this;
                            }
                        });
                    });
                });
            }

            $(function() {
                $("#table").rowspan(0); 
                $("#table").rowspan(1);
            });

        </script>