1、只保留整数直接去掉小数部份
<script type="text/javascript"> var str = 6.2233; var str2 = parseInt(str); alert(str2);//6 </script>
2、只向下取整(也是丢弃小数部份和parseInt()一样)
<script type="text/javascript"> var str = 6.6233; var str2 = Math.floor(str); alert(str2);//6 </script>
3、向上取整(只要超过整数就加1,即只要有小数整数就+1)
<script type="text/javascript"> var str = 6.2233; var str2 = Math.ceil(str); alert(str2);//7 </script>
4、四舍五入取整数(小数部份大于等于5整数才+1,小于5整数不变)
<script type="text/javascript"> var str = 6.2233; var str2 = Math.round(str); alert(str2);//6 </script>
<script type="text/javascript"> var str = 6.6222; var str2 = Math.round(str); alert(str2);//7 </script>
5、取绝对值
<script type="text/javascript"> var str = -6.2233; var str2 = Math.abs(str); alert(str2);//6.2233 </script>
6、取两数之中的最小者
<script type="text/javascript"> var str = 6; var str3 = 10; var str2 = Math.min(str,str3); alert(str2);//6 </script>
7、取两数之中的最大者
<script type="text/javascript"> var str = 6; var str3 = 10; var str2 = Math.max(str,str3); alert(str2);//10 </script>
8、取随机数(从下限值到上限值)
<script type="text/javascript"> var lower = 6; var upper = 10; var str2 = Math.floor(Math.random() * (upper - lower + 1)) + lower; alert(str2); </script>
9、小数部分取几位小数
<script type="text/javascript"> var str = 6.2233; var str2 = str.toFixed(2); alert(str2);//6.22 </script>