<!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> <title>无标题页</title> <script type="text/javascript"> function showMessage() { if(document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value==1) { alert("你好，你选择了第 1 个"); document.getElementById("divMessage").innerText=document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value; } else if(document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value==2) { alert("你好，你选择了第 2 个"); document.getElementById("divMessage").innerText=document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value; } else if(document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value==3) { alert("你好，你选择了第 3 个"); document.getElementById("divMessage").innerText=document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value; } else if(document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value==4) { alert("你好，你选择了第 4 个"); document.getElementById("divMessage").innerText=document.getElementById("selectID").options[document.getElementById("selectID").selectedIndex].value; } } </script> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> </head> <body> <select id="selectID" onchange="return showMessage()"> <option value="0">-----请选择----</option> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> </select> <div id="divMessage"></div> </body> </html>
无标题页
原文：http://www.cnblogs.com/subtract/p/3787931.html