用户将输入信用卡的到期日并检查当前日期。
<html>
<script>
var today = new Date();
var month = today.getMonth();
var year = today.getFullYear();
</script>
<body>
<input type="date" id="date" name="trip" value="2018-10-13" min="" max="2020-12-31" />
</body>
</html>
您可以使用 Javascript Date 实例。假设您可以确保用户以2018-10-13格式输入日期，您可以添加一个侦听器来检测用户何时添加了日期，并将该日期与今天的日期进行比较：
<script>
document.getElementById("dateInput").addEventListener("change", function() {
var dateEntered = new Date(input);
console.log(dateEntered); //e.g. Fri Oct 12 2018 00:00:00 GMT+0000 (GMT Standard Time)
var today = new Date();
console.log(today); //e.g. Thu Oct 11 2018 00:00:00 GMT+0000 (GMT Standard Time)
console.log(dateEntered > today); // If true, means dateEntered is after today's date, meaning the credit card has not expired.
});
</script>