js模板字面量，数字

作者：@kuaiquxie
作者的github：https://github.com/bitebita
本文为作者原创，如需转载，请注明出处：https://www.cnblogs.com/dzwj/p/15864842.html

字符串插值

<!DOCTYPE html>
<html>
<body>

<h2>JavaScript 模板字面量</h2>

<p>模板字面量允许字符串中的变量：</p>

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

<p>Internet Explorer 不支持模板字面量。</p>

<script>
var firstName = "John";
var lastName = "Doe";

var text = `Welcome ${firstName}, ${lastName}!`;

document.getElementById("demo").innerHTML = text;
</script>

</body>
</html>

模板字面量

<!DOCTYPE html>
<html>
<body>

<h2>JavaScript 模板字面量</h2>

<p>模板字面量允许字符串中的变量：</p>

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

<p>Internet Explorer 不支持模板字面量。</p>

<script>
let header = "Templates Literals";
let tags = ["template literals", "javascript", "es6"];

let html = `<h2>${header}</h2><ul>`;

for (const x of tags) {
  html += `<li>${x}</li>`;
}

html += `</ul>`;
document.getElementById("demo").innerHTML = html;
</script>

</body>
</html>

确定是否是数

<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 数字</h1>

<p>您可使用全局 JavaScript 函数 isNaN() 来确定某个值是否是数：</p>

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

<script>
var x = 100 / "Apple";
document.getElementById("demo").innerHTML = isNaN(x);
</script>

</body>
</html>

超出数字范围

<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 数字</h1>

<p>Infinity （或 -Infinity）是 JavaScript 在计算数时超出最大可能数范围时返回的值：</p>

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

<script>
var myNumber = 2; 
var txt = "";
while (myNumber != Infinity) {
   myNumber = myNumber * myNumber;
   txt = txt + myNumber + "<br>";
}
document.getElementById("demo").innerHTML = txt;
</script>

</body>
</html>