javascript table美化鼠标滑动单元格变色

orbitz-like behavior for hovering over table cells

.cssguycomments {background:#eee;border:#ddd;padding:8px;margin-bottom:40px;}
.cssguycomments p {font:normal 12px/18px verdana;}

table {border-collapse:collapse;}
thead th {
font:bold 13px/18px georgia;
text-align:left;
background:#fff4c6;
color:#333;
padding:8px 16px 8px 8px;
border-right:1px solid #fff;
border-bottom:1px solid #fff;
}
thead th.null {background:#fff;}
tbody th {
font:bold 12px/15px georgia;
text-align:left;
background:#fff9e1;
color:#333;
padding:8px;
border-bottom:1px solid #f3f0e4;
border-right:1px solid #fff;
}
tbody td {
font:normal 12px/15px georgia;
color:#333;
padding:8px;
border-right:1px solid #f3f0e4;
border-bottom:1px solid #f3f0e4;
}
/* 这3个是关键 --cssrain.cn */
tbody td.on {background:green;}
thead th.on {background:red;}
tbody th.on {background:red;}


/*
For functions getElementsByClassName, addClassName, and removeClassName
Copyright Robert Nyman, http://www.robertnyman.com
Free to use if this text is included
*/
function addLoadEvent(func) {
var oldonload = window.onload;
if (typeof window.onload != 'function') {
window.onload = func;
} else {
window.onload = function() {
oldonload();
func();
}
}
}

function getElementsByClassName(className, tag, elm){
var testClass = new RegExp("(^|\\s)" + className + "(\\s|$)");
var tag = tag || "*";
var elm = elm || document;
var elements = (tag == "*" && elm.all)? elm.all : elm.getElementsByTagName(tag);
var returnElements = [];
var current;
var length = elements.length;
for(var i=0; i 0)? " " : "") + className;
}
return elm.className;
}

function removeClassName(elm, className){
var classToRemove = new RegExp(("(^|\\s)" + className + "(\\s|$)"), "i");
elm.className = elm.className.replace(classToRemove, "").replace(/^\s+|\s+$/g, "");
return elm.className;
}

function makeTheTableHeadsHighlight() {
// get all the td's in the heart of the table...
var table = document.getElementById('rockartists');
var tbody = table.getElementsByTagName('tbody');
var tbodytds = table.getElementsByTagName('td');

// and loop through them...
for (var i=0; i