<!DOCTYPE html>
<html>

    <head>
        <meta charset="UTF-8">
        <title></title>
    </head>

    <body>
        <select id="year"></select><select id="month"></select><select id="day"></select></body>

</html>
<script>
    var year = document.getElementById("year");
    var month = document.getElementById("month");
    var day = document.getElementById("day");

    var time = new Date();
    year_now = time.getFullYear();

    for(var i = year_now - 100; i < year_now + 100; i++) {
        year.innerHTML += "<option>" + i + "</option>"
    }
    for(var i = 1; i < 13; i++) {
        month.innerHTML += "<option>" + i + "</option>";
    }

    function days(max) {
        day.innerHTML = "";
        for(var i = 1; i <= max; i++) {
            day.innerHTML += "<option value='"+i+"'>" + i + "</option>";
        }
    }
    
    year.onchange = function(){
        if( month.selectedOptions[0].innerHTML==1   ||
            month.selectedOptions[0].innerHTML==3   ||
            month.selectedOptions[0].innerHTML==5   ||
            month.selectedOptions[0].innerHTML==7   ||
            month.selectedOptions[0].innerHTML==8   ||
            month.selectedOptions[0].innerHTML==10  ||
            month.selectedOptions[0].innerHTML==12 
        ){
            days(31);
        }else if(
            month.selectedOptions[0].innerHTML==4   ||
            month.selectedOptions[0].innerHTML==6   ||
            month.selectedOptions[0].innerHTML==9   ||
            month.selectedOptions[0].innerHTML==11  
        ){
            days(30);
        }else{
            var year_selected = year.selectedOptions[0].innerHTML;
            if((year_selected%4==0&&year_selected%100!=0)||year_selected%400==0){
                days(29);
            }else{
                days(28);
            }
        }
    }
    month.onchange = function(){
        if( month.selectedOptions[0].innerHTML==1   ||
            month.selectedOptions[0].innerHTML==3   ||
            month.selectedOptions[0].innerHTML==5   ||
            month.selectedOptions[0].innerHTML==7   ||
            month.selectedOptions[0].innerHTML==8   ||
            month.selectedOptions[0].innerHTML==10  ||
            month.selectedOptions[0].innerHTML==12 
        ){
            days(31);
        }else if(
            month.selectedOptions[0].innerHTML==4   ||
            month.selectedOptions[0].innerHTML==6   ||
            month.selectedOptions[0].innerHTML==9   ||
            month.selectedOptions[0].innerHTML==11  
        ){
            days(30);
        }else{
            var year_selected = year.selectedOptions[0].innerHTML;
            if((year_selected%4==0&&year_selected%100!=0)||year_selected%400==0){
                days(29);
            }else{
                days(28);
            }
        }
    }
</script>

 

posted on 2017-09-29 23:45  我勒个去YCQ  阅读(364)  评论(0编辑  收藏  举报