“Ctrl+/”
“F11/ESC”
<!DOCTYPE html>
<html>
<body>
<p>全局变量在任何脚本和函数内均可访问。</p>
<p id="demo"></p>
<script>
var carName = "Volvo";
myFunction();
function myFunction() {
document.getElementById("demo").innerHTML =
"I can display " + carName;
}
</script>
</body>
</html>