ASP文件上传神功 第一重(招势图加内功心法)

类别:Asp 点击:0 评论:0 推荐:

第一重:单个图片上传到数据库

  这个问题已经不是什么新鲜问题了,网上也有大把的教程,但大多数是授人以鱼,而不授人以渔,经过辛苦的资料收集,思考,调试,整理,我基本上已经把这个问题从原理上搞清楚了,现在根据我自己的理解,在范例程序的基础上,加以解释,希望能对部分网友(比我还菜的:-))有所帮助。

  请诸位大虾能对其中的不正或不良这处予以指正。

  程序中stream对象的用法上参考了“化境HTTP上传程序 Version 2.0”在代码,在此对稻香老农梁无惧表示衷心的感谢和由衷的敬意。

  我想循序渐进,今天先讲一个简单的,单个图片文件保存到数据库

这个范例共包括三个ASP文件和一个数据库(一个表),全部在同一目录下。

1、tblImage 表结构(ACCESS 2000)

  sn     自动编号 序列号
  content-type 文本   图片类型
  image    OLE 对象 图片数据

2、SimpleImageToData.asp:上传表单及保存图片到数据库的代码部分,主要文件。

<%@ Language=VBScript %>
<% option explicit %>

<%
 '从一个完整路径中析出文件名称
 function getFileNamefromPath(strPath)
  getFileNamefromPath = mid(strPath,instrrev(strPath,"\")+1)
 end function

 '定义数据库连接字符串
 dim cnstr
 cnstr = "driver={Microsoft Access Driver (*.mdb)};dbq=" & server.MapPath("./upload.mdb")
%>

<HTML>
 <HEAD>
  <title>单个图像保存到数据库</title>
  <meta http-equiv="Content-Type" content="text/html; charset=gb2312">
 </HEAD>
 <body>
<p><a href="SimpleImageToData.asp">上传图片</a>
 <a href="ShowImageListFromData.asp">显示图片</a><hr></p>
 
<%
 if request.ServerVariables("REQUEST_METHOD") = "POST" then

  dim sCome, sGo, binData, strData
  dim posB, posE, posSB, posSE
  dim binCrlf
  dim strPath, strFileName, strContentType
  
  binCrlf = chrb(13)&chrb(10)   '定义一个单字节的回车换行符
  
  set sCome = server.CreateObject("adodb.stream")
  sCome.Type = 1  '指定返回数据类型 adTypeBinary=1,adTypeText=2
  sCome.Mode = 3  '指定打开模式 adModeRead=1,adModeWrite=2,adModeReadWrite=3
  sCome.Open
  sCome.Write request.BinaryRead(request.TotalBytes)
  
  sCome.Position = 0
  binData = sCome.Read
  
  'response.BinaryWrite binData    '调试用:显示提交的所有数据
  'response.Write "<hr>"        '调试用
  
  set sGo = server.CreateObject("adodb.stream")
  sGo.Type = 1
  sGo.Mode = 3
  sGo.Open
  
  posB = 1
  posB = instrb(posB,binData,binCrlf)
  posE = instrb(posB+1,binData,binCrlf)
  'response.Write posB & " | " & posE & "<br>"
  
  sCome.Position = posB+1
  sCome.CopyTo sGo,posE-posB-2
  sGo.Position = 0
  sGo.Type = 2
  sGo.Charset = "gb2312"
  strData = sGo.ReadText
  sGo.Close
  
  'response.Write strData & "<hr>"
  
  posSB = 1
  posSB = instr(posSB,strData,"filename=""") + len("filename=""")
  posSE = instr(posSB,strData,"""")
  
  if posSE > posSB then
   strPath = mid(strData,posSB,posSE-posSB)
   'response.Write "本地路径:" & strPath & "<br>"
   'response.Write "文件名:" & getFileNamefromPath(strPath) & "<br>"
   
   posB = posE
   posE = instrb(posB+1,binData,binCrlf)
   'response.Write posB & " | " & posE & "<br>"
   
   sGo.Type = 1
   sGo.Mode = 3
   sGo.Open

   sCome.Position = posB
   sCome.CopyTo sGo,posE-posB-1

   sGo.Position = 0
   sGo.Type = 2
   sGo.Charset = "gb2312"
   strData = sGo.ReadText
   sGo.Close
   
   strContentType = mid(strData,16)   '此处因为固定的,所以省略查找 :-)
   'response.Write "图片类型:" & strContentType & "<hr>"
   
   posB = posE+2
   posE = instrb(posB+1,binData,binCrlf)
   'response.Write posB & " | " & posE & "<br>"
   
   sGo.Type = 1
   sGo.Mode = 3
   sGo.Open

   sCome.Position = posB+1
   sCome.CopyTo sGo,posE-posB-2
   
   sGo.Position = 0
   strData = sGo.Read
   sGo.Close
  
   'response.Write lenb(strData) & "<br>"
       
   dim cn, rs, sql
   set cn = server.CreateObject("adodb.connection")
   cn.Open cnstr
   set rs = server.CreateObject("adodb.recordset")
   sql = "select * from tblImage"
   rs.Open sql,cn,1,3
   rs.AddNew
   rs.Fields("content-type").Value = strContentType
   rs.Fields("image").AppendChunk strData
   rs.Update
   rs.Close
   set rs = nothing
   cn.Close
   set cn = nothing
   response.Write "图片保存成功!" & "<br>"
  else
   response.Write "没有上传图片!" & "<br>"
  end if
  
  set sGo = nothing
  sCome.Close
  set sCome = nothing  
 else
%>
  <form id="frmUpload" name="frmUpload" action="SimpleImageToData.asp" method="post" target="_self" enctype="multipart/form-data">
   <INPUT id="filImage" type="file" name="filImage" size="40">
   <BR>
   <INPUT id="btnUpload" type="submit" value="Upload" name="btnUpload">
  </form>
<%
 end if
%>
 </body>
</HTML>

3、ShowImageListFromData.asp

<%@ Language=VBScript %>
<% option explicit %>

<html>
<head>
  <title>显示数据库中已有图片的列表</title>
  <meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head>
<body>
<p><a href="SimpleImageToData.asp">上传图片</a>
 <a href="ShowImageListFromData.asp">显示图片</a><hr></p>
<table border=0 cellpadding=2 cellspacing=2>
 <tr>
  <td valign=top>
  <%
   dim cnstr
   cnstr = "driver={Microsoft Access Driver (*.mdb)};dbq=" & server.MapPath("./upload.mdb")
   
   dim cn, sql, rs
   set cn = server.CreateObject("adodb.connection")
   cn.Open cnstr
   sql = "select sn,[content-type],image from tblImage"
   set rs = cn.Execute(sql)
   
   response.Write "<table border=1 cellspacing=2 cellpadding=5>"
   response.Write "<tr>"
   response.Write "<th>序列号</th><th>图片类型</th><th>图片</th>"
   response.Write "</tr>"
   
   do until rs.eof
    response.Write "<tr>"
    response.Write "<td>" & rs("sn") & "</td>"
    response.Write "<td>" & rs("content-type") & "</td>"
    response.Write "<td><a href='ShowImageListFromData.asp?sn=" & rs("sn") & "'>看图</a></td>"
    response.Write "</tr>"
    rs.movenext
   loop
   
   response.Write "</table>"
   
   cn.Close
   set cn = nothing
  %>
  </td>
  <td valign=top>
  <%
   dim sn
   sn = request.QueryString("sn")
   if sn = "" then
    response.Write "没有指定图片!"
   else
    response.Write "<img border=1 src=ShowImageFromData.asp?sn=" & sn & ">"
   end if
  %>
  </td>
 </tr>
</table>
</body>
</html>

4、ShowImageFromData.asp

<%@ Language=VBScript %>
<% option explicit %>

<%
 dim sn
 sn = request.QueryString("sn")
 if sn = "" then response.End
 
 dim cnstr
 cnstr = "driver={Microsoft Access Driver (*.mdb)};dbq=" & server.MapPath("./upload.mdb")
 
 dim cn, sql, rs
 set cn = server.CreateObject("adodb.connection")
 cn.Open cnstr
 sql = "select sn,[content-type],image from tblImage where sn=" & cint(sn)
 set rs = cn.Execute(sql)
 
 response.ContentType = rs("content-type")
 response.BinaryWrite rs("image")
 
 set rs = nothing
 cn.Close
 set cn = nothing
%>

待续...

本文地址:http://com.8s8s.com/it/it9145.htm