通用于ie和firefox的函数 GetCurrentStyle (obj, prop)

function GetCurrentStyle (obj, prop) {	if (obj.currentStyle) {		return obj.currentStyle[prop];	}	else if (window.getComputedStyle) {		prop = prop.replace (/([A-Z])/g, "-$1");		prop = prop.toLowerCase ();		return window.getComputedStyle (obj, "").getPropertyValue(prop);	}	return null;}