cms's getStyle (getComputedStyle/ currentStyle)

headに書くと動かんからDOM構築を待つように書きかえないとだ(このまま使うなら不要)。 addListener 関数を作って併記するか、内部で書き分けるか。はてさて。

by ethertank

HTML

modify from: <a href="https://gist.github.com/369133" title="Get computed styles — Gist">Get computed styles — Gist</a>

JavaScript

function getStyle(el, styleProp) {
    var value, defaultView = el.ownerDocument.defaultView;

    if (defaultView && defaultView.getComputedStyle) {
        // sanitize property name to css notation (hypen separated words eg. font-Size)
        styleProp = styleProp.replace(/([A-Z])/g, "-$1").toLowerCase();
        return defaultView.getComputedStyle(el, null).getPropertyValue(styleProp);
    } else if (el.currentStyle) { // IE
        // sanitize property name to camelCase
        styleProp = styleProp.replace(/\-(\w)/g, function(str, letter) {
            return letter.toUpperCase();
        });
        value = el.currentStyle[styleProp];
        // convert other units to pixels on IE
        if (/^\d+(em|pt|%|ex)?$/i.test(value)) {
            return (function(value) {
                var oldLeft = el.style.left,
                    oldRsLeft = el.runtimeStyle.left;
                el.runtimeStyle.left = el.currentStyle.left;
                el.style.left = value || 0;
                value = el.style.pixelLeft + "px";
                el.style.left = oldLeft;
                el.runtimeStyle.left = oldRsLeft;
                return value;
            })(value);
        }
        return value;
    }
}




// test

var div = document.createElement("div");
div.style.color = "blue";
document.body.appendChild(div);
    
alert(
    getStyle(document.body, "color") + "\n" +
    getStyle(div, "color")
);