Upload Files Without COM v3
Allows you to upload multiple files and fields without purchasing or registering COM objects. Great for shared hosts that frown upon 3rd Party com objects or charge an arm and a leg for them. This script provides an object oriented interface using classes for easier development. The power that this script has over others is that it does not use dictionary objects to store the uploaded files. It also harnesses the power of ADODB to prepare and save binary data to the file system with quick speeds. This is the script that you have been looking for. You can get a really good feel for how the script is used just by reading through the FAQ and examples provided. This script has been tailored to meet the requests of developers who have used previouse versions. The code is comented very well and comes along with examples of how to do common operations, as well as a FAQ. Bugs from version 2 have been fixed, or otherwise throw exceptions to the user giving them details of how to correct the problem (such as giving permission to the internet user account). Memory is managed more efficiently in version 3 that allows for more scaleablity and larger files. By the request of a few developers, progress bars are now supported to notify the user how much information has been received by the server. A website for support has also been created where you can get help from the author, other users of the script, and get any recent revisions or additional examples as they become available.
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<style> BLOCKQUOTE { background-color: #ccccff; }
</style>
<center>
<h1>Upload Files without COM</h1>
<h4>Created by Lewis Moten</h4>
</center>
<p>
I have gone through the internet and my email trying to collect many of the
questions that I have received in the past concerning version 1 and 2 of the
Upload Files without COM scripts. I have also tried to display examples for
common scenarios that many of you will use. Please read through this FAQ fully
before sending me a question.
</p>
<h2>General Information</h2>
<ol>
<li>
<b>What does it do?</b>
<p>
This script allows you to upload multiple files and fields without purchasing
or registering COM objects. It is ideal for shared hosts that frown upon 3rd
Party com objects or charge an arm and a leg for them.
</p>
<p>
This script provides an object oriented interface using classes for easier
development. The power that this script has over others is that it does not use
dictionary objects to store the uploaded files. It also harnesses the power of
ADODB to prepare and save binary data to the file system with quick speeds.
This is the script that you have been looking for. You can get a really good
feel for how the script is used just by reading through this FAQ.
</p>
<p>
The code is commented very well and comes along with examples of how to do
common operations, as well as the FAQ you are reading now. Bugs from version 2
have been fixed, or otherwise throw exceptions to the user giving them details
of how to correct the problem (such as giving permission to the internet user
account). Memory is managed more efficiently in version 3 that allows for more
scalability and larger files.
</p>
<li>
<b>What is new in version 3?</b>
<p> </p>
<ul>
<li>
Better control over memory management.
<li>
Detailed errors with suggestive fixes for user errors.
<li>
Fixed errors reported by other users that could be duplicated
<li>
File Management (Move, Copy, Rename, Delete)
<li>
Assignment of default file name if none were provided
<LI>
Introduced ability to display upload progress meter
<li>
Method to return a similar unique file name not used within a folder
<li>
Method to return a collection of fields assigned the same field name
<li>
First FAQ was created
<li>
Debug method to write contents of posted data for developers and
troubleshooting
<li>
Structure documented in separate file.
<li>
Mug shot of the developer</li>
</ul>
<p> </p>
<li>
<b>What are the requirements?</b>
<p>
You should have Microsoft Data Access Components (ADODB) 2.6 or later
installed. Also, you need to have Microsoft Windows Script 5.5 or later
installed as well. Many ISP's have this installed by default. If your ISP does
not have them installed, you can direct them to download the software from
Microsoft's website for free.
</p>
<p>
http://www.microsoft.com/data - Microsoft Data Access Components<br>
http://www.microsoft.com/scripting - Microsoft Windows Script
</p>
<p>
I would also like to point out that you must run this script on a website that
can process ASP scripts. You can not view these scripts from your file system.
You will have to type in a URL in your web browser beginning with http://.
Microsoft provides a web server called Internet Information Server (IIS) for
servers and Personal Web Server for personal computers. Personal Web Server was
made available with Windows NT 4.0 Option Pack, but is compatible with Windows
9x operating systems.
</p>
<p>
http://www.microsoft.com/iis - Internet Information Services<br>
http://www.microsoft.com/ntserver/nts/downloads/recommended/NT4OptPk/default.asp -
Windows NT 4.0 Option Pack
</p>
<li>
<b>How much does your script cost?</b>
<p>
The script is free to use within your website. I do ask that you register this
script at http://upload.lewismoten.com.
Monetary donations (large and small) are accepted through PayPal with my
account, Axiom Studios, Inc. If you would like to donate equipment, hosting
space, or software, please contact me at lewis@moten.com.
</p>
<p>
Make a donation via paypal to lewis@moten.com
</p>
<li>
<b>Can I modify your script?</b>
<p>
Yes, you may modify it for your own website, but you may not publish or
distribute the code without my written permission. Simply put, if you are
making money with my script, I would appreciate some acknowledgement, funds,
hosted space and/or hardware to encourage my development for the open source
community. Email me for more details.
</p>
<li>
<b>How can you claim to upload files without COM?</b>
<p>
I am aware that since version 2, I have used the MDAC components (ADODB) to
speed up the upload process. If you want to get technical, using the Request
object is a COM component. I could rename this script to <i>upload files without
having to install additional COM on most current standard windows operating
systems</i>. Instead, I kept the name simple and to the point. It is the
first thing people start looking for when they need the solution that I
provide.
</p>
<li>
<b>What browsers / operating systems are needed by my visitors?</b>
<p>
Microsoft Internet Explorer 6.0 appears to work fine on the Windows Platform.<br>
Mozilla 1.4 works ok on Windows. I have had problems when dealing with Unicode.<br>
</p>
<p>
I have heard that users with Macintosh computers have problems. If someone has
a spare Mac that they would like to donate, then I would be willing to take the
time to fix up the script to support them.
</p>
</li>
</ol>
<h2>Getting Started</h2>
<ol>
<li>
<b>How do I install the scripts?</b>
<p>
These instructions are written for those of you who have access to the computer
with a default installation of IIS. Some steps may have to be changed according
to your setup.
</p>
<p>
The upload script depends on <b>three</b> different scripts. These are
clsField.asp, clsUpload.asp, and clsProgress.asp. In your website, do the
following:
</p>
<ol>
<li>
Create folder called Upload in your c:\Inetpub\wwwroot directory.
<li>
Copy clsUpload.asp to the folder
<li>
Copy clsField.asp to the folder
<li>
Set the permissions for your Internet Guest Account to have the rites to write,
read, and modify the upload folder.
<li>
Create an ASP page called Form.asp with the following code: <blockquote> <FORM
method="post" encType="multipart/form-data" action="Upload.asp"><br>
<INPUT type="File" name="File1"><br>
<INPUT type="Submit" value="Upload"><br>
</FORM> </blockquote>
<li>
Create an ASP page called Upload.asp with the following code: <blockquote> <!--#INCLUDE
FILE="clsUpload.asp"--><br>
<%<br>
Dim Upload<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & Upload("File1").FileName<br>
Set Upload = Nothing<br>
%><br>
</blockquote>
<li>
Visit the Form.asp page in your browser. http://localhost/Upload/Form.asp
http://localhost/Upload/Form.asp</a></li>
</ol>
<p>
Hopefully, everything worked fine and you are on your way. Some of the steps
may need to be changed, according to the location of your website.
</p>
<li>
<b>How do I setup permissions on the folder I wish to upload to?</b>
<p>
Open up your file explorer and locate the folder that you wish to update files
to. Right mouse click the folder and click Properties. Click the Security tab.
You will see a list of users who have access to the folder. Click the Add
button and locate a user beginning with "IUSR_", it will be followed by the
name of your computer. This is called the Internet Guest Account. When you
click on the user in the list of assigned users, you will need to verify that
they have access to write, modify and read.
</p>
<li>
<b>How do I upload 2 or more files at once?</b>
<p>
Add additional INPUT tags to your form for uploading files. Give each one a
different name, such as File1, File2, etc.
</p>
<blockquote> <INPUT type="file" name="File1"><br>
<INPUT type="file" name="File2"><br>
<INPUT type="file" name="File3"> </blockquote><blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & Upload("File1").FileName<br>
Upload("File2").SaveAs Folder & Upload("File2").FileName<br>
Upload("File3").SaveAs Folder & Upload("File3").FileName<br>
Set Upload = Nothing<br>
</blockquote>
<li>
<b>How do I upload other information in the form at the same time?</b>
<p>
You can add additional input elements that are different types.
</p>
<blockquote> <INPUT type="file" name="File1"><br>
<INPUT type="text" name="Description"> </blockquote><blockquote> Dim
Upload<br>
Dim Description<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
<u>Description = Upload("Description").Value</u><br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & FileName<br>
Set Upload = Nothing<br>
Response.Write "Description: " & Description </blockquote>
<li>
<b>How do I display a progress meter?</b>
<p>
The progress meter is a little tricky, but I have done most of the work
for you in determining how it can be done. When the user clicks the
Submit button, you will need to open a Popup window that will display the
status for the current upload session. Sessions are identified by passing
a query string to both the Popup window, and the ASP file that processes the
upload. This session should be a random number, or you will run the risk
of your users seeing progress for someone else's upload.
</p>
<p>One of the most important rules for the progress window is that you <EM>must</EM>
<STRONG><U>disable session state</U></STRONG> for the ASP page. You can
leave session state active for the rest of your website, but this page can not
use it. If session state is enabled, then your progress window will
appear to hang until the upload has completed. To disable session state
in one page, you can use the following tag at the top of your page: <STRONG><FONT face="Courier New" size="2">
<%@ EnableSessionState=False %></FONT></STRONG></p>
<blockquote><FORM <U>onsubmit=</U><EM>"return UploadForm_submit()"</EM> method="post"
action="Upload.asp" name="UploadForm" encType="multipart/form-data"><BR>
<INPUT type="file" name="File1"><br>
<INPUT type="submit" value="Upload"><BR>
</FORM> </blockquote><blockquote><SCRIPT language="javascript"><BR>
function UploadForm_submit()<BR>
{<BR>
// Create a random session identifier.
<BR>
var Session = new String();
<BR>
Session = Math.floor(Math.random() * 0xFFFFFF).toString(16);
<BR>
<BR>
// append identification of session
<BR>
<U>document.UploadForm.action</U><EM> += "?Session=" + Session;</EM><BR>
<BR>
// open the pop-up window
<BR>
<U>window.open</U>(<EM>"Status.asp?Session=" + Session</EM> ,"upload","width=200,height=200");
<BR>
}<BR>
</SCRIPT></blockquote><blockquote><%@EnableSessionState=False%><BR>
<!--#INCLUDEFILE= "clsProgress.asp"-->< BR> <%<BR>
Dim Progress<BR>
Set Progress = New clsProgress<BR>
Progress.Load<BR>
Response.Write "Uploaded "<BR>
Response.Write Progress.BytesReceived<BR>
Response.Write " of "<BR>
Response.Write Progress.TotalBytes<br>
Set Progress = Nothing<BR>
%><BR>
<SCRIPT language="javascript"><BR>
// reload this page after 1 second.<BR>
window.setTimeout("window.location.reload()", 1000);<BR>
</SCRIPT> </blockquote>
<p>The progress class exposes the basic information about your upload
session. View the structure documentation for a list of all of its
methods and properties. With this information, you can create your own
progress meters. An example progress meter has been included for you with
the original script package called Progress_Status.asp.</p>
<li>
<b>How do I access a collection of fields with the same name?</b>
<p>
A collection is sent when you have a select list that allows for more then one
item to be chosen, or if you have multiple fields with the same name on your
form. In the past, this was a little tricky to access, but now a new feature
has been introduced. You can access an array of fields by calling the
Collection method on the Upload object. Each field of the form is sent, in the
order in which it occurs in the form.
</p>
<blockquote> <SELECT multiple size="3" name="Colors"><br>
<OPTION selected value="#ff0000">Red<br>
<OPTION selected value="#ffffff">White<br>
<OPTION value="#0000ff">Blue<br>
</SELECT> </blockquote><blockquote> Dim Upload<br>
Set Upload = New clsUpload<br>
Dim Colors<br>
Dim Color<br>
<br>
<u>Colors = Upload.Collection("Colors")</u><br>
For Each Color In Colors<br>
Response.Write Color.Value & "<BR>"<br>
Next<br>
<br>
Set Upload = Nothing </blockquote>
</li>
</ol>
<h2>Managing Existing Files</h2>
<ol>
<li>
<b>How do I delete files?</b>
<p>
The upload object has a routine called DeleteFile. Pass the full path to the
file to this routine.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
<u>Upload.DeleteFile Folder & FileName</u><br>
Upload("File1").SaveAs Folder & FileName<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I rename a file in my file system?</b>
<p>
The upload object has a routine called RenameFile. Pass the full path to the
file to this routine, and the new name of the file.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
<u>Upload.RenameFile Folder & FileName, "NewFileName.gif"</u><br>
Upload("File1").SaveAs Folder & FileName<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I copy a file in my file system?</b>
<p>
The upload object has a routine called CopyFile. Pass the full path of the
current file to this routine, and the full path to the target location.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
<u>Upload.CopyFile Folder & FileName, Folder & "NewFileName.gif"</u><br>
Upload("File1").SaveAs Folder & FileName<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I move a file in my file system?</b>
<p>
The upload object has a routine called MoveFile. Pass the full path of the
current file to this routine, and the full path to the target location.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
<u>Upload.MoveFile Folder & FileName, Folder & "NewFileName.gif"</u><br>
Upload("File1").SaveAs Folder & FileName<br>
Set Upload = Nothing </blockquote>
</li>
</ol>
<h2>File Restrictions</h2>
<ol>
<li>
<b>How do I restrict the user from uploading certain file extensions? (EXE, BAT,
COM, VBS, etc.)</b>
<p>
The field object has a property called FileExt. You can check this to verify
that the file extension is valid, or a potential risk.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Dim Ext<br>
Set Upload = New clsUpload<br>
<u>Ext = Upload("File1").FileExt</u><br>
Select Case Ext<br>
Case "GIF", "JPG", "PNG", "BMP"<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & FileName<br>
Case Else<br>
Response.Write "File type not supported."<br>
End Select<br>
Set Upload = Nothing </blockquote>
<p>
Although a filenames extension may be valid, it may still contain harmful
information. Imagine a scenario where a user creates a virus and renames it to
photo.gif. This will get past your file extension validation. You may wish to
use other scripts or components to validate the binary data as well. You can
use another script I crated called <i>Read Image Dimensions</i> to help aid you
in verifying a files actual content when dealing with images. The class
clsImage is included with this distribution of Upload Files without COM.
</p>
<blockquote> Dim Width<br>
Dim Height<br>
Set Upload = New clsUpload<br>
Set Image = New clsImage<br>
Image.DataStream = Upload.Fields("File1").BinaryData<br>
<u>Select Case Image.ImageType</u><br>
Case "GIF", "JPG", "PNG", "BMP"<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & FileName<br>
Case Else<br>
Response.Write "File type not supported."<br>
End Select<br>
Set Image = Nothing<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I get image pixel dimensions (height x width)</b>
<p>
I have published another script that supports this called <i>Read Image Dimensions</i>.
It is included with this distribution as clsImage.asp.
</p>
<p>
With the Image Script, you can either read a file from the file system, or pass
the binary data of the image to be read to it. You can then verify if the image
size falls within your requirements and notify the user if it does not.
</p>
<blockquote> Dim Width<br>
Dim Height<br>
Set Upload = New clsUpload<br>
Set Image = New clsImage<br>
Image.DataStream = Upload.Fields("File1").BinaryData<br>
<u>If Image.Width > 640 Then</u><br>
Response.Write "Image is too wide. It must be 640x480
or less."<br>
<u>ElseIf Image.Height > 480 Then</u><br>
Response.Write "Image is too high. It must be 640x480
or less."<br>
Else<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & FileName<br>
End If<br>
Set Image = Nothing<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I limit the file size that a user can upload?</b>
<p>
Each field that you upload has a Length property. You can check the length to
make sure it is a specific size or less.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
<u>If Upload("File1").Length <= 1048576</u><br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & FileName<br>
Else<br>
Response.Write "File size must be 1 megabyte or less"<br>
End If<br>
Set Upload = Nothing </blockquote>
<li>
<b>Can the user select mulitple files at once?</b>
<p>
No. This is a restriction of the input element. However, you can have multiple
input elements on one page. The visitor will have to populate each one with the
location of the file on there computer.
</p>
</li>
</ol>
<h2>Working with Databases</h2>
<ol>
<li>
<b>How do I upload a file into a database?</b>
<p>
The Field object has a property called BLOB. This can be saved directly into
the database.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Connection<br>
Dim RecordSet<br>
Dim ConnectionString<br>
<br>
<i>' One of these may work for you, depending on your systems configuration</i><br>
ConnectionString = "DRIVER=Microsoft Access Driver (*.mdb);DBQ=" &
Server.MapPath("Files.mdb")<br>
ConnectionString = "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=" &
Server.MapPath("Files.mdb")<br>
<br>
Set Upload = New clsUpload<br>
FileName = objUpload.Fields("File1").FileName<br>
<br>
Set Connection = Server.CreateObject("ADODB.Connection")<br>
Set RecordSet = Server.CreateObject("ADODB.Recordset")<br>
<br>
Connection.Open ConnectionString<br>
<br>
RecordSet.Open "Files", Connection, 3, 3<br>
<br>
RecordSet.AddNew<br>
<br>
RecordSet.Fields("FileName").Value = objUpload.Fields("File1").FileName<br>
RecordSet.Fields("FileSize").Value = objUpload.Fields("File1").Length<br>
RecordSet.Fields("ContentType").Value = objUpload.Fields("File1").ContentType<br>
<u>RecordSet.Fields("BinaryData").AppendChunk objUpload("File1").BLOB & ChrB(0)</u><br>
<br>
RecordSet.Update<br>
<br>
RecordSet.Close<br>
<br>
Set RecordSet = Nothing<br>
Set Connection = Nothing<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I retrieve a file from the database?</b>
<p>
You can use the BinaryWrite method on the Response Object
</p>
<blockquote> Dim Connection<br>
Dim RecordSet<br>
Dim ConnectionString<br>
Dim FileID<br>
Dim Sql<br>
<br>
<i>' One of these may work for you, depending on your systems configuration</i><br>
ConnectionString = "DRIVER=Microsoft Access Driver (*.mdb);DBQ=" &
Server.MapPath("Files.mdb")<br>
ConnectionString = "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=" &
Server.MapPath("Files.mdb")<br>
<br>
FileID = Request.QueryString("FileID")<br>
<br>
<br>
Set Connection = Server.CreateObject("ADODB.Connection")<br>
Set RecordSet = Server.CreateObject("ADODB.Recordset")<br>
<br>
Connection.Open ConnectionString<br>
<br>
Sql = "SELECT FileName, ContentType, BinaryData FROM Files WHERE FileID = "
& FileID<br>
<br>
RecordSet.Open Sql, Connection, 3, 3<br>
<br>
If Not RecordSet.EOF Then<br>
Response.AddHeader "content-disposition", "attachment;
filename=" & RecordSet("FileName")<br>
Response.AddHeader "content-length",
RecordSet("BinaryData").ActualSize<br>
Response.ContentType = RecordSet("ContentType")<br>
<u>Response.BinaryWrite RecordSet("BinaryData")</u><br>
Else<br>
Response.Write("File could not be found")<br>
End If<br>
<br>
RecordSet.Close<br>
Connection.Close<br>
<br>
Set RecordSet = Nothing<br>
Set Connection = Nothing<br>
</blockquote>
<li>
<b>How do I display a picture from the database?</b>
<p>
You can work with the code that retrieves files from the database. Just
reference the web page in your image tag.
</p>
<blockquote> <IMG src="Download.asp?FileID=327"> </blockquote>
<li>
<b>How do I setup permissions on the Access database I wish to write in?</b>
<p>
This is very similar to setting up permissions for folders. Rather then
right-clicking on the folder, you can right-click on the file itself. The only
permissions that you will need to verify are that they have access to read
and modify the file.
</p>
<li>
<b>What kind of data type should I use with a Microsoft Access database?</b>
<p>
Microsoft Access can store binary data in fields defined as <u>OLE Object</u>.
</p>
<li>
<b>What kind of data type should I use with a Microsoft SQL Server?</b>
<p>
SQL Server has a few data types to store binary data. The quickest one to
identify is the binary data type. This one is like a varchar data type (where
you specify how long your data can be). The data type that I prefer to use is <u>the
image data type</u> (similar to the text and ntext fields). The image data
type holds a 16 byte pointer to your actual binary data and has a size limit of
roughly 2 gigabytes. If you wish to restrict your data so that a file can not
be stored that is greater then a certain size, then go with the binary data
type, other wise - use image.
</p>
</li>
</ol>
<h2>File Names</h2>
<ol>
<li>
<b>How do I let the user choose the name of the file?</b>
<p>
You can provide an extra text field and use this when saving the file. When the
user sends the file over, you can then save the file with the suggested name.
</p>
<blockquote> <INPUT type="file" name="File1"><br>
<INPUT type="text" name="FileName"> </blockquote><blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
FileName = Upload("FileName").Value<br>
Folder = Server.MapPath("Uploads") & "\"<br>
Upload("File1").SaveAs Folder & FileName<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I make the file unique, if it already exists?</b>
<p>
The upload class provides a method called <i>UniqueName</i>. You may pass the
proposed file name, and the path of the folder that you wish to store it
within. If a duplicate file name already exists within the folder, it will
iterate through an index until it finds a name that does not yet exist.
</p>
<p>
If you upload a file called Photo.JPG 3 times, and use the UniqueName method
each time, then you will have 3 files with the following names: Photo.JPG,
Photo[1].JPG, Photo[2].JPG.
</p>
<blockquote> Dim Upload<br>
Dim FileName<br>
Dim Folder<br>
Set Upload = New clsUpload<br>
FileName = Upload("File1").FileName<br>
Folder = Server.MapPath("Uploads") & "\"<br>
FileName = Upload.UniqueName(Folder, FileName)<br>
Upload("File1").SaveAs Folder & FileName<br>
Set Upload = Nothing </blockquote>
<li>
<b>What happens if the file exists on the file system?</b>
<p>
The file is overwritten. You can use the UniqueName method to make sure that
files are not over written by assigning them different names if a file with the
same name already exists.
</p>
</li>
</ol>
<h2>Performance</h2>
<ol>
<li>
<b>Is there anything I can do to speed up uploads?</b>
<p>
You can modify the number of bytes read at a time when the posted form data is
read. This property can be found within clsUpload.asp. By
default, the setting is 64 KB. Remember, as you decrease the value,
the buffer is read and processed more often. If you are saving progress
information, then a file is opened and written to each time as well.
However, if you make the buffer too large, then your clients' progress window
will not appear to get new information as often.
</p>
<p>
Do not setup your buffer to be under 100 bytes, or you may risk not being able
to parse the data property for each field that had been posted to the web page.
</p>
<BLOCKQUOTE> Const BufferSize = &H10000 </BLOCKQUOTE>
<p>For your reference:
</p>
<table border="1" align="center">
<tr>
<td><FONT size="2"><STRONG>Kilobytes</STRONG></FONT></td>
<td><FONT size="2"><STRONG>Bytes</STRONG></FONT></td>
<td><FONT size="2"><STRONG>Hex Value</STRONG></FONT></td>
</tr>
<tr>
<td><FONT size="2">1 KB</FONT></td>
<td><FONT size="2">1024</FONT></td>
<td><FONT size="2">&H400</FONT></td>
</tr>
<tr>
<td><FONT size="2">2 KB</FONT></td>
<td><FONT size="2">2048</FONT></td>
<td><FONT size="2">&H800</FONT></td>
</tr>
<tr>
<td><FONT size="2">4 KB</FONT></td>
<td><FONT size="2">4096</FONT></td>
<td><FONT size="2">&H1000</FONT></td>
</tr>
<tr>
<td><FONT size="2">8 KB</FONT></td>
<td><FONT size="2">8192</FONT></td>
<td><FONT size="2">&H2000</FONT></td>
</tr>
<tr>
<td><FONT size="2">16 KB</FONT></td>
<td><FONT size="2">16384</FONT></td>
<td><FONT size="2">&H4000</FONT></td>
</tr>
<tr>
<td><FONT size="2">32 KB</FONT></td>
<td><FONT size="2">32768</FONT></td>
<td><FONT size="2">&H8000</FONT></td>
</tr>
<tr>
<td bgColor="#ccff99"><FONT size="2">64 KB</FONT></td>
<td bgColor="#ccff99"><FONT size="2">65536</FONT></td>
<td bgColor="#ccff99"><FONT size="2">&H10000</FONT></td>
</tr>
<tr>
<td><FONT size="2">128 KB</FONT></td>
<td><FONT size="2">131072</FONT></td>
<td><FONT size="2">&H20000</FONT></td>
</tr>
<tr>
<td><FONT size="2">256 KB</FONT></td>
<td><FONT size="2">262144</FONT></td>
<td><FONT size="2">&H40000</FONT></td>
</tr>
</table>
<li>
<b>How large can my files be?</b>
<p>
The answer is not known. Some developers have mentioned that the script has
worked perfectly with files over 100 MB for version 2. Others have mentioned
that it begins to have problems when the files go up to that size, or even over
1 MB. It depends on your web servers' resources and connection speed to the
visitor. It also depends if you are working with the latest version, as each
one usually increases in performance.
</p>
<p>
As each version is released, it becomes more scaleable to allow larger file
sizes. Hopefully, this version will allow more developers to approach the 100
MB test with success.
</p>
<p>
Version 2 helped increase the speed and take less memory to upload a file by
introducing ADO Streams to handle conversion. Version 3 improves on the memory
by constantly going to a central location to retrieve binary data rather then
make small copies of it for each file uploaded. Also, data is not parsed until
your code asks for it.
</p>
<li>
<b>How well does vbScript handle the String Concatenations?</b>
<p>
One of the downfalls of vbScript (and Visual Basic) is that in order to
concatenate a string, you must copy it into memory twice. Take the following
for example: (myString = myString & "xxxxx"). It is copied once to be
assigned, and the other time is copied as the string being assigned.
</p>
<p>
This was a large problem with version 1 and slowed things down a lot when
pulling binary content from the posted form data. The process was sped up by
assigning a large chunk of the data to an ADODB.Stream object to convert the
binary data for us. A lot of you who used version 1 were amazed when version 2
came out.
</p>
<p>
Two internal functions still remain that have a lot of concatenation
(CStrU and CStrB). These two methods convert between Unicode and ASCII strings
one character at a time. This is one of the last bottle necks left due to
limitations of ASP. As long as your text values are small, the methods will not
spend too much of your servers resources to convert the data. If you post a
large resume in a TEXTAREA, then you may begin to see noticeable results.
</p>
</li>
</ol>
<h2>Miscellaneous Questions</h2>
<ol>
<li>
<b>Does the script support double-byte character file names?</b>
<p>
Part of this question depends on your web server, another part depends on your
web browser, and the last part depends on how well I've put my code together
without knowing how to deal with Unicode. Your file names and content of the
file may not transfer properly. I make no guarantees.
</p>
<p>
With that said, I don't have much to go on. From what I can understand, you may
have to modify Meta tags and code pages on the server before you can properly
test if this script supports double byte characters. I tried copying some
double-byte characters from the internet and pasting it into one of my file
names. After I had uploaded it with MSIE, the file was renamed. I tried this on
both Windows XP and a Windows 2000 Server with the same exact results.
</p>
<p>
I tried copying the characters into the contents of a text file, and saved the
file as Unicode. After uploading the file, I was still able to see the correct
Unicode characters within it.
</p>
<p>
I tried the same tests with Mozilla 1.4. It replaced all the Unicode characters
in the filename to underscore characters. Also, it only sent one byte of the
files data across the line.
</p>
<p>
If you have had success or suggestions, please share your findings by sending
me an email.
</p>
<li>
<b>How do I remove your signature from the error messages?</b>
<p>
Just do a search for any portion of the signature in the ASP code. You may find
it within an area where the class initializes. Please do not pass the code
along to others after you had made changes.
</p>
<li>
<b>What else can your script do?</b>
<p>
If you are really interesting the full potential of what the script can
do, take a look at the source code. It is commented very well so that even
beginners can get a rough idea about what is happening.
</p>
<li>
<b>Does your script work with ChilisoftASP or iASP?</b>
<p>
I do not know. If you have ChilisoftASP or iASP, please try it out and tell me
what the results are.
</p>
<p>
http://wwws.sun.com/software/chilisoft/index.html - Sun ONE Active Server
Pages 4.0</a> - Chili!soft.ASP<br>
http://www.halcyonsoft.com/ - Halcyon Software - iASP, Instant ASP<br>
</p>
<li>
<b>Where can I get detailed information about uploading files?</b>
<p>
You can find this information if you search the internet for <u>RFC 1867</u>.
(A.k.a. Request for Comments). As taken from the document itself, here is its
explanation:
</p>
<blockquote> This memo defines an Experimental Protocol for the Internet community.
This memo does not specify an Internet standard of any kind. Discussion and
suggestions for improvement are requested. Distribution of this memo is
unlimited. </blockquote>
<p>
This was back in 1995. RFC 1867 is no longer experimental. It is a widely
accepted Internet standard.
</p>
</li>
</ol>
<h2>Trouble Shooting</h2>
<ol>
<li>
<b>What is the work-around to "Cannot call BinaryRead after using Request.Form"?</b>
<p>
This error has been caught in version 3 and gives details for working around
it. This problem occurs because the Request.BinaryRead method may only be
called once. Both the Request.Form and Upload class call this method. You have
to make a choice. Do you want to use the Upload class to get your form data, or
the standard Request.Form?
</p>
<p>
Most people run into this problem because they want to request other data
posted on the form besides the file itself. The Upload class does support this.
Use the following code to help you out.
</p>
<blockquote> Dim Upload<br>
Dim Description<br>
Set Upload = New clsUpload<br>
Description = Upload("Description").Value<br>
Set Upload = Nothing </blockquote>
<li>
<b>How do I use Request.Form? I get Request object error 'ASP 0207 : 80004005'
Cannot use Request.Form</b>
<p>
See: <i>What is the work-around to "Cannot call BinaryRead after using
Request.Form"?</i>
</p>
<li>
<b>What do I do if I get a Microsoft VBScript compilation error '800a0401' Expected
end of statement?</b>
<p>
Your web server is not running with the latest version of Microsoft Windows
Script. This script has been verified with vbScript version 5.5 and above.
Microsoft Windows Script is available free of charge from the Microsoft web
site.
</p>
<p>
http://www.microsoft.com/scripting - Microsoft Windows Script
</p>
<li>
<b>My host does not allow the use of the File System Object. What can I do?</b>
<p>
Some web service providers do not allow you to create the
Scripting.FileSystemObject object, or they restrict it to have limited
functionality. If this is becoming a problem for you, then you can disable this
feature. Look in clsUpload.asp for a Const variable named
FileSystemObjectEnabled. Set this value to false and you should be ready to go.
</p>
<blockquote> <u>Const FileSystemObjectEnabled = False</u> </blockquote>
<p>
The file system object was used to add new features in this version that allow
you to move, copy, delete, and rename files. It also aids in identifying a
unique name for the file, and verifies the upload directory exists. It is not
required in order to upload files or save them to the file system.
</p>
<li>
<b>I have error 8000### ?</b>
<p>
If an error isn't addressed within this FAQ, and the error message returned
does not help you, then please contact me (lewis@moten.com).
</p>
<li>
<b>I fixed line ###, what do I do?</b>
<p>
Please contact me with the reason the code was changed and the source code that
you updated it with. (lewis@moten.com)
</p>
<li>
<b>How can I read the raw data of what is actually coming from the user?</b>
<p>
For debugging purposes, I have created a DebugText method that you may use. I
advise to use this with small text files, as the time to debug increases
according to the amount of data that it has to parse. If you have a browser
that is giving you problems, then you can send me the results returned from
this method and I can look at the results and determine if I can come up with a
solution to your problem.
</p>
<blockquote> Dim Upload<br>
Set Upload = New clsUpload<br>
Response.Write Upload.DebugText<br>
Set Upload = Nothing<br>
</blockquote>
<li>
<b>My websites host doesn't allow me to use the file system object. What do I need
to do?</b>
<p>
Open the clsUpload.asp file and look for the line that assigns a value to
FileSystemObjectEnabled. You will need to set this value to false.
If you disable the file system object, then you will not be able to display
progress meters or interact with the file system through the upload
class. However, you will still be able to save files to the file system
and/or database.
</p>
<blockquote> Const FileSystemObjectEnabled = False<br>
</blockquote>
</li>
</ol>
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