<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> </head> <body> <h1>hello world</h1> <script> // alert弹框 括号里面参数弹框内的文字内容 alert("你好"); </script> </body> </html>
