要完成此效果需要两个步骤
第一步：把如下代码加入到<head>区域中
<script>
function calc() {
var dnum = ((eval(document.res.inpa.value)) / 2);
var i;
var pol;
var inum = (Math.round(dnum));
if (inum == dnum) {
document.res.rses.value="数字: " + (eval(document.res.inpa.value)) + " 成立\n\n";
}
else {
document.res.rses.value="数字: " + (eval(document.res.inpa.value)) + " 不成立\n\n";
}
document.res.rses.value += "因子:\n\n";
var num = Math.round(eval(document.res.inpa.value));
for (i = 2; i < (num / 2); i++) {
var chkd = Math.round(num / i);
var inn = Math.round(num / i);
var outt = (num / i);
if (inn == outt && chkd > i) {
document.res.rses.value = document.res.rses.value + "(" + (num/i) + "," + i + ")";
}
}
}
function numbersonly() {
if (event.keyCode < 48 || event.keyCode > 57) return false;
}
</script>
第二步：把如下代码加入到<body>区域中
<form name="res">
<div align="center">
<input type=text value="0" name="inpa" onkeypress="return numbersonly()">
<input type=button name="bt1" value="计算" onClick="calc()">
<br>
结果 <br>
<textarea name="rses" cols="20" rows="10" value="nothing"> |
