javaScript年份下拉列表框内容为当前年份及前后50年

<script language="javascript" type="text/javascript"> 
window.onload=function(){ 
//设置年份的选择 
var myDate= new Date(); 
var startYear=myDate.getFullYear()-50;//起始年份 
var endYear=myDate.getFullYear()+50;//结束年份 
var obj=document.getElementById(‘myYear‘) 
for (var i=startYear;i<=endYear;i++) 
{ 
obj.options.add(new Option(i,i)); 
} 
obj.options[obj.options.length-51].selected=1; 
} 
</script> 
<select id="myYear"></select> 

window.onload=function(){ 
    //设置年份的选择 
    var myDate= new Date(); 
    var startYear=myDate.getFullYear()-2;//起始年份 
    var endYear=myDate.getFullYear()+1;//结束年份 
    var obj=document.getElementById(‘myYear‘) 
    for (var i=startYear;i<=endYear;i++) 
    { 
        obj.options.add(new Option(i,i)); 
    } 
    obj.options[obj.options.length-2].selected=1; 
}