function window_onload()
{
    var myForm = document.form1;
    var nowDate = new Date();
    myForm.firstDay.options[nowDate.getDate()-1].selected = true;
    myForm.secondDay.options[nowDate.getDate()-1].selected =true;
    myForm.secondMonth.options[nowDate.getMonth()].selected =true;
    myForm.firstMonth.options[nowDate.getMonth()].selected = true;
    myForm.firstYear.options[nowDate.getFullYear()-1970].selected =true;
    myForm.secondYear.options[nowDate.getFullYear()-1970].selected =true;
}
//可以执行，返回firstDay，secondDay.options【】对象的值为当前时间，，
function window_onload()
{
    var myForm = document.form1;
    var nowDate = new Date();
    myForm.firstDay.options[nowDate.getDate()-1].selected = true;
    myForm.firstMonth.options[nowDate.getMonth()].selected = true;
    myForm.firstYear.options[nowDate.getFullYear()-1970].selected =true;
    myForm.secondDay.options[nowDate.getDate()-1].selected =true;
    myForm.secondMonth.options[nowDate.getMonth()].selected =true;    
    myForm.secondYear.options[nowDate.getFullYear()-1970].selected =true;
}

顺序更改后，firstDay 正常返回当前日期，secondDay则无法返回当前日期，为什么？？？