点击运行
<!DOCTYPE html> <html> <body> <h1>JavaScript 数字</h1> <p>如果您对两个数相加，结果将是一个数：</p> <p id="demo"></p> <script> var x = 10; var y = 20; var z = x + y; document.getElementById("demo").innerHTML = z; </script> </body> </html>
运行结果
