code:
![](https://www.cnblogs.com/Images/OutliningIndicators/ContractedBlock.gif)
<html>
<head>
<title></title>
<script language=”javascript">
//生成数字下拉列表(选中项,起始数字,结束数字)
function CreateOption(str1, str2, str3) {
var CreateOption = "";
for (var i = str2; i <= str3; i++) {
CreateOption += "<option value=" + i;
if (str1 == i) {
CreateOption += "\" selected>" + i + "</option>";
}
else {
CreateOption += "\">" + i + "</option>";
}
}
document.write(CreateOption);
}
</script>
</head>
<body>
<select >
<script type="text/javascript">CreateOption('1','1','20')</script>
</select>
</body>
</html>