示例代码：
<html> <title>通过选择项显示不同的结果-www.jb200.com</title> <head> <script type="text/javascript"> function showdiv() { var doc=document; var citytext=doc.getElementById("city").value; var div1=doc.getElementById("div1"); var div2=doc.getElementById("div2"); var div3=doc.getElementById("div3"); switch (citytext) { case "广州": div1.setAttribute("style","display"); div2.setAttribute("style","display:none"); div3.setAttribute("style","display:none"); doc.getElementById("text1").value=citytext; break; case "南昌": div1.setAttribute("style","display:none"); div2.setAttribute("style","display"); div3.setAttribute("style","display:none"); doc.getElementById("text2").value=citytext; break; case "沈阳": div1.setAttribute("style","display:none"); div2.setAttribute("style","display:none"); div3.setAttribute("style","display"); doc.getElementById("text3").value=citytext; break; } } </script> </head> <body> <select title="城市" id="city" onchange="showdiv()"> <option selected value="广州">广州</option> <option value="南昌">南昌</option> <option value="沈阳">沈阳</option> </select> <div id="div1" style="display:none" >您选择了广东的省会<input type="text" id="text1" value=""/></div> <div id="div2" style="display:none" >您选择了江西的省会<input type="text" id="text2" value=""/></div> <div id="div3" style="display:none" >您选择了辽宁的省会<input type="text" id="text3" value=""/></div> </body> </html>