javascript 執行減法運算

在 javascript 執行 float 相減時，可能會發生 9.700000000000001 的情形
為防止這個情形發生，必需加上 .toFixed()

例如:
var i = 9.8;
i = (i - 0.1).toFixed(1); // i => 9.7

Get viewport size (Nice)

var w = window,
d = document,
e = d.documentElement,
g = d.getElementsByTagName('body')[0],
x = w.innerWidth || e.clientWidth || g.clientWidth,
y = w.innerHeight|| e.clientHeight|| g.clientHeight;
alert(x);
alert(y);

Reference url: http://stackoverflow.com/questions/3437786/how-to-get-web-page-size-browser-window-size-screen-size-in-a-cross-browser-wa

Post data to a new window with full screen

Javascript Example:


function postDataToNewWindow() {
var myform = document.createElement("form");
myform.setAttribute("method", "post");
myform.setAttribute("action", "verifyCredential.asp");
myform.setAttribute("target", "_custom");

var hiddenField = document.createElement("input");
hiddenField.setAttribute("type", "hidden");
hiddenField.setAttribute("name", "credential");
hiddenField.setAttribute("id", "credential");
hiddenField.setAttribute("value", "2.0");

myform.appendChild(hiddenField);
document.body.appendChild(myform);
window.open("", "_custom", "fullscreen=yes");
myform.submit();
}