为什么表单验证程序显示错误还提交?
//我想实现当title中的内容为空,禁止提交,可不知为什么虽然提示 "请填写产品类型 ",但还是提交了,我也不知为什么,希望高手指点,谢谢了!!!!!11 
  <!DOCTYPE   HTML   PUBLIC    "-//W3C//DTD   HTML   4.01   Transitional//EN ">  
  <%@   codepage   =   936   LCID   =   2052   %>  
  <%   if   Session( "exemple_status ")    <>     "login "   then   response.redirect    "login.asp "   %>  
  <!--#include   file= "pagefoot.asp "-->  
  <!--#include   file= "header.asp "-->  
  <script      language= "JavaScript ">  
 function      CheckLoginForm() 
 {    
 	if   (document.form1.title.value      ==    " ") 
 	{ 
 		alert( "请填写产品类型! "); 
 		document.form1.title.focus(); 
 		return   false; 
 	} 
 } 
  </script>  
  <table   width= "100% "   border= "0 "   cellspacing= "0 "   cellpadding= "0 "   bgcolor= "#336699 ">  <tr>  <td>  
  <img   src= "images/bnrlist.gif "   alt= " "   width= "400 "   height= "30 "   border= "0 ">  </td>  </tr>  </table>  
  <%strsql   = "select   *   from   [pro_type] "    
 set   rs=server.createobject( "adodb.recordset ") 
 set   conn=server.createobject( "adodb.connection ") 
 conn.open   xDb_Conn_Str 
 rs.open   strsql,conn,3,3 
  '如果第一次进入就显示下面代码!!! 
 if   request.servervariables( "request_method ")= "GET "   then 
 %>  
  <form      name= "form1 "      action=ptype_add.asp   method= "post "      >  
  <table      bgColor= "#000000 "   border= "0 "   align=center   width=100%>  
        <tr>  
           <td   vAlign= "top "   width= "25% "   bgColor= "#f7f7f7 "      >  
             类型名称: <input   type=text   value= " "   name=title   >  
              </td>  </tr>  
     <tr>  <td   vAlign= "top "   width= "5% "   bgColor= "#f7f7f7 "      align=center>  
              <input   type   =    "submit "      value   =    "添加 "      onclick= "CheckLoginForm() ">  
              <input   type   =    "button "      value   =    "返回 "   onClick   =    "javascript:window.history.go(-1) "   >  
              </td>  
  </tr>  
  </table>  
  </form>  
  <%else 
  '点吉添加按纽 
 rs.addnew 
 rs( "type_name ")=trim(request( "title ")) 
    rs.update 
 response.write( " <script   language= 'JavaScript '> alert( '添加成功!! ');location.href= 'pro_typelist.asp '; </script>  ") 
 end   if 
 rs.close 
 set   rs=nothing 
 %>  
  <!--#include   file= "footer.asp "-->
------解决方案--------------------onclick= "CheckLoginForm() "改为 
 onclick= &quo