voicexml的menu例子
例子来源：http://www.optimsys.cz/support/examples/example12.php
主要的menu的应用
menu下有choice，根据按dtmf值或者说出的值进行选择哪个choice，然后跳转到相应的form，执行form里的语音

<?xml version="1.0" encoding="UTF-8"?><vxml version="2.0" xmlns="http://www.w3.org/2001/vxml"><meta name="description" content="menu example"/><meta name="author" content="OptimSys, s.r.o., Czech Republic (http://www.optimsys.cz)"/><meta name="copyright" content="free for any purpose"/><menu dtmf="true">  <prompt>    Welcome to main menu. Say the name of the required section or    <enumerate>      press <value expr="_dtmf"/> for <value expr="_prompt"/>,    </enumerate>  </prompt>  <choice next="#news">    news  </choice>  <choice next="#sport">    sport  </choice>  <choice next="#weather">    weather forecast  </choice>  <noinput> Please say one of <enumerate/> </noinput>  <nomatch> I don't understand you. Please say one of <enumerate/> </nomatch></menu><form id="news">  <block> Welcome to news. Nothing is here for now. </block></form><form id="sport">  <block> Welcome to sport section. Nothing is here for now. </block></form><form id="weather">  <block> Welcome to weather forecast. Weather will be either nice or bad. </block></form></vxml>