选择下拉框里面内容自动跳转特定页面

function searchMail(){ 
  if(document.getElementById("search").value ==""){ 
   alert("请输入要搜索的关键字"); 
   document.getElementById("search").focus(); 
  }else{ 
   location="index.cfm?event=ehMail.dspComposeMessage&search="+document.getElementById("search").value+"&searchType="+document.getElementById("searchType").value; 
  } 
} 

搜索&nbsp;<input type="text" size="30" name="search" id="search" value="<cfif isdefined("rc.search")><cfoutput>#rc.search#</cfoutput></cfif>" />&nbsp;按&nbsp; 
<select name="searchType" id="searchType"> 
     <option value="title"<cfif isdefined("searchType") and searchType eq "title"> selected="selected"</cfif>>邮件主题</option> 
     <option value="mail"<cfif isdefined("searchType") and searchType eq "mail"> selected="selected"</cfif>>收件人信箱</option> 
     <option value="desc"<cfif isdefined("searchType") and searchType eq "desc"> selected="selected"</cfif>>邮件内容</option> 
</select> 
      <input type="button" style="font-size:80%;" name="searchButton" id="searchButton" value="确 认"  />