<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> </head> <body> <select size="1" id="qq" onchange="change()"> <option selected="selected" value="11">汉堡</option> <option value="22">鸡腿</option> <option value="33">可乐</option> </select><br /> <br /> <p id="pp" style="font-size:24px; color:red;">价格：8元</p> </body> </html> <script> function change() { var a = document.getElementById("qq").value; var p =document.getElementById("pp"); if(a=="11") { p.innerHTML="价格：8元"; } else if(a=="22") { p.innerHTML="价格：10元"; } else { p.innerHTML="价格：3元"; } } </script>