前端验证两次密码是否一致

HTML

<form action="/s.php" method="post">
设置密码：<input type="password" id="p1" required>
确认密码：<input type="password" id="p2" required onblur="checkpassword()">
<input type="submit" value="提交">
</form>

JS

<script>
function checkpassword() {
    var password = document.getElementById("p1").value;
    var repassword = document.getElementById("p2").value;
    if(password!=repassword){
        alert("设置密码与确认密码不匹配！")
        document.getElementById('p1').value = "";
        document.getElementById('p2').value = "";
    }
}
</script>