求救！！！！我做的论坛发帖完后为什么要重新刷新一下页面才能显示我发的帖子（代码附下）

我做的论坛在addnew.aspx页面中发帖完后重新指向bbs.aspx后为什么要重新刷新一下页面才能显示我发的帖子（代码附下），各位大哥大姐救救我吧：）
<%@import namespace="system.data.oledb"%>
<%@import namespace="system.data"%>
<%@ Page Language="vb" debug="true" %>
<body>
<!--#include virtual="head.inc"-->
<script language=vb runat=server>
sub page_load(sender as object,e as eventargs)
if session("username") = ""  then
response.redirect("bbs_login.aspx")
end if
end sub
sub Addnew_Subject_Submit(sender as object,e as eventargs)
    '=============上传图片===============================
dim i as integer
dim finfo as string
dim img as string
dim postedfile as httppostedfile=request.files(I)
'================================================
if postedfile.contentlength>0 then
dim filesplit() as string=split(postedfile.filename,"\")
dim filename as string=filesplit(filesplit.length-1)
postedfile.saveas(server.mappath("db\uploadfile")&"\"&filename)
dim imgpath as string ="db\uploadfile\"&filename
img="<img src="+imgpath+" border=0>"
end if
'=======================================提交文本信息==
dim mycommand as OLEDBcommand
    dim conn as OLEDBconnection
dim updatestring as string
dim subjectstr as string= subject.text
dim flage as string="subject"
    dim description as string=text1.text
    dim username as string=session("username")
    dim userhead as string=session("userhead")
    dim bianmian as string
    bianmian = request("banmian")
    '================格式转换======================
    subjectstr=subjectstr.Replace("&","&amp;")
subjectstr=subjectstr.Replace("<","&lt;")
subjectstr =subjectstr.Replace(">","&gt;")
subjectstr =subjectstr.Replace(chr(32),"&nbsp;")
subjectstr =subjectstr.Replace("'","’")
subjectstr=subjectstr.Replace(chr(13),"<br>")
subjectstr=subjectstr.Replace(chr(10),"<br>")

'================格式转换======================
dim contentstr as string=content.text
    contentstr=contentstr.Replace("&","&amp;")
contentstr=contentstr.Replace("<","&lt;")
contentstr =contentstr.Replace(">","&gt;")
contentstr =contentstr.Replace(chr(32),"&nbsp;")
contentstr =contentstr.Replace("'","’")
contentstr=contentstr.Replace(chr(13),"<br>")
contentstr=contentstr.Replace(chr(10),"<br>")
'============
description=description.Replace("&","&amp;")
description=description.Replace("<","&lt;")
description =description.Replace(">","&gt;")
description=description.Replace(chr(32),"&nbsp;")
description=description.Replace("'","’")
description=description.Replace(chr(13),"<br>")


'=====================将转换后的字符串保存到数据库===
if username="" then
username="未知"
end if
updatestring="insert into content (subject,content,subdate,flage,subname,headimg,hitnum,replynum,img,imgdescription,bname)values('"+subjectstr+"','"+contentstr+"',NOW(),'"+flage+"','"+username+"','"+userhead+"',0,0,'"+img+"','"+description+"','"+bianmian+"')"
conn=new OLEDBconnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source="&server.mappath("db\bbs.mdb"))
    mycommand=new OLEDBcommand(updatestring,conn)
    conn.open()
    mycommand.executenonquery()
dim url as string
url = "bbs.aspx?Artname=" & request("banmian")  //为什么这里指向了bbs.aspx但要刷
    response.Redirect(url)                          //新后才能显示刚发的帖子？？？
end sub
</script>
<form enctype="multipart/form-data"  runat="server" ID="Form1" style="font-size:9pt;text-align:center" >
  当前版面: <asp:Label id="bianmian" runat="server"/>
  文章标题：<asp:textbox ID="SUBJECT" runat="server"  TextMode="SingleLine"  MaxLength="30" size="30"/><br>
  文章内容：<ASP:TEXTBOX  ID="content"   runat="server"  textmode="multiline" rows="10" Columns="60"/>
<br>
上传图片：<input type="file" id="fileup1" runat="server"  SIZE=50 maxlength=50><br>
    图片说明：<asp:textbox id="text1" runat="server" textmode="singleline" maxlength="30" size="30"/><asp:Panel ID="button_panel" runat="server"  HorizontalAlign="center"><br>
  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<asp:button ID="submit" runat="server" OnClick="Addnew_Subject_Submit" Text="发表这篇文章"/>
 
</asp:Panel>
<asp:Label ID="statues" Runat="server"></asp:Label>
<asp:RequiredFieldValidator
 ID="REVPASSWORD"
  ControlToValidate="subject"
   Display=None
    InitialValue=""
     ErrorMessage="文章名必须填写!"
      Runat=server>
  </asp:RequiredFieldValidator>
<asp:RequiredFieldValidator
 ID="Requiredfieldvalidator1"
  ControlToValidate="content"
   Display=None
    InitialValue=""
     ErrorMessage="文章内容必须填写!"
      Runat=server>
  </asp:RequiredFieldValidator>
<asp:ValidationSummary
  ID="ValidationSummary1"
   runat=server
       EnableViewState=False
        ShowSummary=False
      HeaderText="文章提交失败，请注意以下规则:"
       ShowMessageBox=True
        Font-Name=verdana
         Font-Size=9pt> </asp:ValidationSummary>       
<table width="7%" border="0" align="center" cellpadding="0" cellspacing="1"  class=unnamed3>
         <tr>
           <td width="93%" class=bar ><a href="javascript:history.back(1)">返回上一页</a></td>
         </tr>
  </table>
  <p>&nbsp;</p>
</form>
<!--#include virtual="foot.inc"-->
</body>