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

<h1>JavaScript 字符串</h1>

<p>字符串写在单引号或双引号内:</p>

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

<script>
let carName1 = "Volvo XC60";  // 双引号
let carName2 = 'Volvo XC60';  // 单引号

document.getElementById("demo").innerHTML =
carName1 + " " + carName2; 
</script>

</body>
</html>
运行结果: