代码示例:(标识:eg_js_number_nan_concat)
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 数字</h1>

<p>假如您在数学运算中使用了 NaN,则结果可能是级联:</p>

<p id="demo"></p>

<script>
var x = NaN;
var y = "5";
document.getElementById("demo").innerHTML = x + y;
</script>

</body>
</html>
运行结果: