NaN
所以,可以根据这样的特性,判断数是否为 NaN 。
在第二日计算问题,当日期为月末时,使用如下方式可以使其加一
var currentDate = new Date();
var nextDate = +currentDate + 1000*60*60*24;
nextDate = new Date(nextDate);
console.log(nextDate);
例子
<form id="dateForm">
<input type="date" id="date" placeholder="请输入日期">
<button type="button" id="btn" onclick="computed()">计算第二日</button>
<p id="result"></p>
</form>
<script type='text/javascript'>
function computed() {
var currentDate = document.getElementById('date').value;
var result = document.getElementById('result');
result.innerHTML= '';
if(currentDate.value == ""){
window.alert('请输入计算日期!'.currentDate.value);
return false;
}
currentDate = new Date(currentDate);
currentDate = +currentDate + 1000*60*60*24;
currentDate = new Date(currentDate);
var nextDate = currentDate.getFullYear()+"-"+(currentDate.getMonth()+1)+"-"+currentDate.getDate();
var year = currentDate.getFullYear();
if(year !== year){
window.alert('请选择日期!');
return false;
}
result.innerHTML = "第二日:" + nextDate;
}
</script>