验证码在网上有很多 楼主可以自己搜索一下
主要的原理就是
产生随即数 用SESSION 保存
在和用户输入的比较。。
我现在就是不知道如何。。“在和用户输入的比较。。”这个怎么做。。。：（
，老是不对。。。多谢那么多朋友教学，如果我贴出来。。。结合上面朋友给的“生成数字”程序，如何修改下面的这个才对呢？？
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<!--#include file="dd_conn.asp"-->
<%
if request("send")="ok" then
username=trim(request.form("username"))
usermail=trim(request.form("usermail"))
if username="" or request.form("Comments")="" then
response.write "<script language='javascript'>"
response.write "alert('填写资料不完整，请检查后重新输入！');"
response.write "location.href='javascript:history.go(-1)';"
response.write "</script>"
response.end
end if
if checktxt(request.form("username"))<>request.form("username") then
response.write "<script language='javascript'>"
response.write "alert('您输入的用户名中含有非法字符，请检查后重新输入！');"
response.write "location.href='javascript:history.go(-1)';"
response.write "</script>"
response.end
end if
if mailyes=0 then '邮箱为必填时检查邮箱是否合法
if checktxt(request.form("usermail"))<>request.form("usermail") then
response.write "<script language='javascript'>"
response.write "alert('您输入的邮箱中含有非法字符，请检查后重新输入！');"
response.write "location.href='javascript:history.go(-1)';"
response.write "</script>"
response.end
end if
if Instr(usermail,".")<=0 or Instr(usermail,"@")<=0 or len(usermail)<10 or len(usermail)>50 then
response.write "<script language='javascript'>"
response.write "alert('您输入的电子邮件地址格式不正确，请检查后重新输入！');"
response.write "location.href='javascript:history.go(-1)';"
response.write "</script>"
response.end
end if
end if
if len(request.form("Comments"))>maxlength then
response.write "<script language='javascript'>"
response.write "alert('留言内容太长了，请不要超过"&maxlength&"个字符！');"
response.write "location.href='javascript:history.go(-1)';"
response.write "</script>"
response.end
end if
set rs=Server.CreateObject("ADODB.RecordSet")
sql="select * from Feedback where online='1' order by Postdate desc"
rs.open sql,conn,1,3
rs.Addnew
rs("username")=Request("username")
rs("comments")=Request("comments")
rs("usermail")=Request("usermail")
rs("face")=Request("face")
rs("pic")=Request("pic")
rs("url")=Request("url")
rs("qq")=Request("qq")
view=cstr(view)
if view<>"0" then view="1"
rs("online")=view
rs("IP")=Request.serverVariables("REMOTE_ADDR")
rs.Update
rs.close
set rs=nothing
response.write "<script language='javascript'>"
if view="0" then
response.write "alert('留言提交成功，留言须经管理员审核才能发布。');"
else
response.write "alert('留言提交成功，单击“确定”返回留言列表！');"
end if
response.write "location.href='index.asp';"
response.write "</script>"
response.end
end if
%>
<HTML><HEAD>
<TITLE><%=sitename%></TITLE>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<meta name="description" content="<%=sitename%>">
<meta name="keywords" content="<%=sitename%>">
<link rel="stylesheet" href="book.css" type="text/css">
</HEAD>
<center>
<!--#include file="book_top.asp"-->
<table width="779" border=0 cellspacing=0 cellpadding=0 align=center bgcolor="#FFFFFF" class="grayline">
<tr><td align=center height=50>
<img border=0 src=images/write.gif> <a href=index.asp><img border=0 src=images/read.gif title="我要看留言"></a>
</td></tr>
<tr><td>
<form action=write.asp method=post name="book">
<table cellSpacing="1" borderColorDark="#ffffff" cellPadding="4" width="680" align="center" bgColor="#000000" borderColorLight="#000000" border="0">
<tr bgColor="#ebebeb">
<td width="20%" align=right>您的姓名：</td>
<td ><input type=text name="UserName" size="30" maxlength=16>
<font color="#FF0000">*</font></td>
</tr>
<tr bgColor="#ebebeb">
<td width="20%" align=right>您的邮箱：</td>
<td ><input type=text name="UserMail" size="30" maxlength=50>
<%if mailyes=0 then%><font color="#FF0000">*</font><%end if%></td>
</tr>
<tr bgColor="#ebebeb">
<td width="20%" align=right>您的网站：</td>
<td><input type=text value="http://" name="url" size="30" maxlength=100></td>
</tr>
<tr bgColor="#ebebeb">
<td width="20%" align=right>其它联系方式：</td>
<td><input type=text value="" name="QQ" size="30" maxlength=100> （如QQ、MSN等）</td>
</tr>
<tr bgColor="#ebebeb">
<td width="20%" align=right>留言内容：<br><font color=red>（<%=maxlength%>字以内）</font></td>
<td><textarea name="Comments" rows="7" cols="66" style="overflow:auto;"></textarea></td>
</tr>
<tr bgColor="#ebebeb">
<td width="20%" align=right>请选择表情：</td>
<td>
<input type="radio" value="1" name="face" checked><img border=0 src="images/face/face1.gif">
<input type="radio" value="2" name="face"><img border=0 src="images/face/face2.gif">
<input type="radio" value="3" name="face"><img border=0 src="images/face/face3.gif">
<input type="radio" value="4" name="face"><img border=0 src="images/face/face4.gif">
<input type="radio" value="5" name="face"><img border=0 src="images/face/face5.gif">
<input type="radio" value="6" name="face"><img border=0 src="images/face/face6.gif">
<input type="radio" value="7" name="face"><img border=0 src="images/face/face7.gif">
<input type="radio" value="8" name="face"><img border=0 src="images/face/face8.gif">
<input type="radio" value="9" name="face"><img border=0 src="images/face/face9.gif">
<input type="radio" value="10" name="face"><img border=0 src="images/face/face10.gif">
<br>
<input type="radio" value="11" name="face"><img border=0 src="images/face/face11.gif">
<input type="radio" value="12" name="face"><img border=0 src="images/face/face12.gif">
<input type="radio" value="13" name="face"><img border=0 src="images/face/face13.gif">
<input type="radio" value="14" name="face"><img border=0 src="images/face/face14.gif">
<input type="radio" value="15" name="face"><img border=0 src="images/face/face15.gif">
<input type="radio" value="16" name="face"><img border=0 src="images/face/face16.gif">
<input type="radio" value="17" name="face"><img border=0 src="images/face/face17.gif">
<input type="radio" value="18" name="face"><img border=0 src="images/face/face18.gif">
<input type="radio" value="19" name="face"><img border=0 src="images/face/face19.gif">
<input type="radio" value="20" name="face"><img border=0 src="images/face/face20.gif">
</td>
</tr>
<tr bgColor="#ebebeb">
<td width="20%" align=right>请选择头像：</td>
<td>
<input type="radio" value="1" name="pic" checked><img border=0 src="images/face/pic1.gif" width=60>
<input type="radio" value="2" name="pic"><img border=0 src="images/face/pic2.gif" width=60>
<input type="radio" value="3" name="pic"><img border=0 src="images/face/pic3.gif" width=60>
<input type="radio" value="4" name="pic"><img border=0 src="images/face/pic4.gif" width=60>
<input type="radio" value="5" name="pic"><img border=0 src="images/face/pic5.gif" width=60>
<br>
<input type="radio" value="6" name="pic"><img border=0 src="images/face/pic6.gif" width=60>
<input type="radio" value="7" name="pic"><img border=0 src="images/face/pic7.gif" width=60>
<input type="radio" value="8" name="pic"><img border=0 src="images/face/pic8.gif" width=60>
<input type="radio" value="9" name="pic"><img border=0 src="images/face/pic9.gif" width=60>
<input type="radio" value="10" name="pic"><img border=0 src="images/face/pic10.gif" width=60>
</td>
</tr>
<tr bgColor="#ebebeb">
<td colSpan="2"><input type="submit" value="提交留言" name="Submit">
<input type="reset" value="重新填写" name="Submit2"><input type=hidden name=send value=ok></td>
</tr>
</table>
</form>
</table>
<!--#include file="book_down.asp"-->
</center>
</body>
</html>
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[此贴子已经被作者于2007-2-6 18:16:04编辑过]
