<html lang = "en">
<head>
<meta charset = "UTF-8">
<title> 实时 监听 input 值 的 变化 </title>
</head>
</script>
<script type = "text / javascript ">
function sum (obj) { var a = document.getElementById (" accountReceivable "); ? ? ? ? ? ? var b = document.getElementById ("vipdiscount"); var somme = a.value * b.value;
document.getElementById ('testid'). innerText = parseInt (somme);
Receipts.value = parseInt (somme);
}
</script>
<body> <table style = "border-collapse: separ; border-spacing: 0px 10px;">
<tr>
<td align = "right"> 应收 现金 ： </td>
<td> < input id = "accountReceivable" name = "accountReceivable" value = "1" οnkeyup = "sum (this);" > </td>
<td> 元 ， 折扣 ： </td>
<td> <input id = "vipdiscount" name = "vipdiscount" value = "1" οnkeyup = "sum (this);" > </td>
<td align = "right"> 实 收 ： </td>
<td> <input id = "receipts" readonly = "true" style = "border: 0px"> </td>
<td>元 </td>
<td> 消费 类型 ： <select id = "
<tr> <span id = "testid"> $ {accountReceivable} * $ {vipdiscount} </span> </tr>
</table>
</body>
</html>