User:Mike Dillon/Scripts/autonumber.js

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Documentation for this user script can be added at User:Mike Dillon/Scripts/autonumber.

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/* <pre><nowiki> */

$(function () {
    function firstCell(row) {
        for (var n in row.childNodes) {
            var c = row.childNodes[n];
            if (/^t[dh]$/i.test(c.tagName)) return c;
        }
    }

    var tables = getElementsByClassName(document.getElementById("bodyContent"), "table", "autonumber");
    for (var n in tables) {
        var t = tables[n];

        var rownum = 1;
        for (var m = 0; m < t.rows.length; m++) {
            var r = t.rows[m];

            var c = firstCell(r);
            if (!c) continue;

            var newCell;
            if (c.tagName.toLowerCase() == "th") {
                newCell = document.createElement("th");
                newCell.appendChild(document.createTextNode("#"));
                rownum = 1; // Renumber if a header row is seen
            } else {
                newCell = document.createElement("td");
                newCell.appendChild(document.createTextNode(rownum));
                rownum += 1;
            }
            newCell.setAttribute("class", "autonumber-cell");
            r.insertBefore(newCell, r.firstChild);
        }
    }
});

/* </nowiki></pre> */