突出表格行

window.onload (){
var rows=document.getElementsByTagName("td");//tr可换为变量，表示不同的元素
    for (var i=0; i<rows.length; i++)
    {
        rows. ()
        {
            this.style.f;
            this.style.backgroundColor="blue";
        }
        rows. ()
        {
            this.style.f;
            this.style.backgroundColor="white";
        }
    }