为什么结果是0123

<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Math </title>
<script type="text/javascript">
var mystr=[3.3,-0.1,-9.9,8.9];
for(var substr in mystr)
{
    document.write(Math.ceil(substr)+"<br>");
}
</script>
</head>
<body>
</body>
</html>

是遍历有问题吗？

_Capricornna

浏览 1123回答 1

1回答

刚毅87

<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Math </title> <script type="text/javascript"> var mystr = [3.3, -0.1, -9.9, 8.9]; for(var substr in mystr) { document.write(Math.ceil(mystr[substr]) + "<br>"); } </script> </head> <body> </body> </html>substr 只是数组的下标,只需把 substr 改为 mystr[substr]即可.

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