jquery - 我需要获取第一个输入的值，然后添加+1，然后将总和放入文本字​​段

Question

这是我现在的代码，但在 acadyearTo 中输出 NaN:

jquery:

<script>
$( document ).ready(function() {
    var sum = parseInt($('#acadyearFrom').val()) + 1;
$('#acadyearTo').val(sum);
 });
</script>

html:

<input type="text" name="acadyearFrom" maxlength="4"  id="acadyearFrom">
<input type="text" name="acadyearTo" maxlength="4" id="acadyearTo">

Answer 1

var sum = parseInt($('#acadyearFrom').val()) + 1; // getting data from one text box, converting into number and adding 1
$('#acadyearTo').val(sum); // setting data to another text box