怎样使用js来验证年龄是否大于18岁
<div class="renzhenglx_div">
<div class="renzheng_left_div" style="line-height: 20px">
生日：</div>
<div class="renzheng_right_div">
<select name="Date_Year" id="Date_Year" class="select_b_div" style="width: auto;">
</select> 年
<select name="birthday_m" id="birthday_m" class="select_b_div" style="width: auto;">
</select> 月
<select name="birthday_d"" id="birthday_d" class="select_b_div" style="width: auto;">
</select> 日
</div>
</div>
[解决办法]
<div class="renzhenglx_div">
<div class="renzheng_left_div" style="line-height: 20px">
生日：</div>
<div class="renzheng_right_div">
<select name="Date_Year" id="Date_Year" class="select_b_div" style="width: auto;">
<script type="text/javascript">
var i;
for (var i = 1980; i <= 2000; i++) document.write('<option value="' + i + '">' + i + '</option>');
</script>
</select> 年
<select name="birthday_m" id="birthday_m" class="select_b_div" style="width: auto;">
<script type="text/javascript">
for (var i = 1; i <= 12; i++) document.write('<option value="' + i + '">' + i + '</option>');
</script>
</select> 月
<select name="birthday_d"" id="birthday_d" class="select_b_div" style="width: auto;">
<script type="text/javascript">
for (var i = 1; i <= 31; i++) document.write('<option value="' + i + '">' + i + '</option>');
function checkage() {
var y =parseInt( document.getElementById('Date_Year').value)
, m = parseInt( document.getElementById('birthday_m').value)-1
, d = parseInt(document.getElementById('birthday_d').value);
var nowday = new Date(), birthday = new Date(y, m, d)
, age = nowday.getFullYear() - birthday.getFullYear() - ((nowday.getMonth() < birthday.getMonth()
[解决办法]
nowday.getMonth() == birthday.getMonth() && nowday.getDate() < birthday.getDate()) ? 1 : 0); ;
alert(age)
}
</script>
</select> 日<input type="button" value="检查年龄" onclick="checkage()" />
</div>
</div>
