1.<input name = "t1">
2.<input name = "t2"><script language="javascript">
var temp = document.al.t1.value;
if temp != "" && Isnumric(temp)
document.all.t2.value = 2 * temp;
</script>
2.<input name = "t2"><script language="javascript">
var temp = document.al.t1.value;
if temp != "" && Isnumric(temp)
document.all.t2.value = 2 * temp;
</script>
解决方案 »
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