【原】获取css属性的计算值

function getStyle(el,p){ 
        if(typeof el=='string') { 
            el=document.getElementById(el); 
        } 
        if (window.getComputedStyle) { 
        //document.defaultView 
            var compStyle = window.getComputedStyle (el, ""); 
        } 
        else { 
            var compStyle = el.currentStyle; 
        } 
        return compStyle[p]; 
 
}