W3School TIY Editor
W3School 在线教程
改变方向
暗黑模式
运行代码
<!DOCTYPE html> <html> <body> <h1>JavaScript 变量</h1> <p id="demo"></p> <script> var price1 = 7; var price2 = 8; var price3 = 12; var total = price1 + price2 + price3; document.getElementById("demo").innerHTML = "总计：" + total; </script> </body> </html>