代码示例:(标识:jsck_state_var_2)
<!DOCTYPE html>
<html>
<body>

<p>将 5 赋给 x,将 6 赋给 y,并显示 x + y 的结果:</p>

<button onclick="myFunction()">试一试</button>

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

<script>
function myFunction() {
  var x = 5;
  var y = 6;
  document.getElementById("demo").innerHTML = x + y;
}
</script>

</body>
</html>
运行结果: