有两种可以用在循环中的语句：break 和 continue。
break 命令可以终止循环的运行，然后继续执行循环之后的代码（如果循环之后有代码的话）。
实例：
<html>
<body>
<script type="text/javascript">
var i=0;
for (i=0;i<=10;i++)
{
if (i==3){break}
document.write("The number is " + i;
document.write("<br />");
}
</script>
</body>
</html>
结果如下：<body>
<script type="text/javascript">
var i=0;
for (i=0;i<=10;i++)
{
if (i==3){break}
document.write("The number is " + i;
document.write("<br />");
}
</script>
</body>
</html>
The number is 0
The number is 1
The number is 2
The number is 1
The number is 2
continue 命令会终止当前的循环，然后从下一个值继续运行。
<html>
<body>
<script type="text/javascript">
var i=0;
for (i=0;i<=10;i++)
{
if (i==3){continue}
document.write("The number is " + i);
document.write("<br />");
}
</script>
</body>
</html>
结果如下：<body>
<script type="text/javascript">
var i=0;
for (i=0;i<=10;i++)
{
if (i==3){continue}
document.write("The number is " + i);
document.write("<br />");
}
</script>
</body>
</html>
The number is 0
The number is 1
The number is 2
The number is 4
The number is 5
The number is 6
The number is 7
The number is 8
The number is 9
The number is 10
The number is 1
The number is 2
The number is 4
The number is 5
The number is 6
The number is 7
The number is 8
The number is 9
The number is 10