HTMLTableElement.rules

The HTMLTableElement.rules property indicates which cell borders to render in the table.

HTMLTableElement.rules = rules;
var rules = HTMLTableElement.rules;

rules is a string with one of the following values:

none

No rules

groups

Lines between groups only

rows

Lines between rows

cols

Lines between cols

all

Lines between all cells

// Turn on all the internal borders of a table
var t = document.getElementById("TableID");
t.rules = "all";

• W3C DOM 2 HTML Specification