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Revision: 36042
at November 17, 2010 04:02 by vedgiee

Initial Code
<%@ Page Trace="False" Language="vb" aspcompat="false" debug="true" validateRequest="false"%> 
<%@ Import Namespace=System.Drawing %>
<%@ Import Namespace=System.Drawing.Imaging %>
<%@ Import Namespace=System %>
<%@ Import Namespace=System.Collections %>
<%@ Import Namespace=System.Web %>
<%@ Import Namespace=System.Web.UI %>
<%@ Import Namespace=System.Web.UI.WebControls %>
<SCRIPT LANGUAGE="VBScript" runat="server">
const Lx = 200	' max width for thumbnails
const Ly = 240	' max height for thumbnails
    Dim upload_dir = "uploads/"    ' directory to upload file
    Dim upload_original = ""
    ' filename to save original as (suffix added by script)
    Dim upload_thumb = "_thumb"  ' filename to save thumbnail as (suffix added by script)
    Const upload_max_size = 250 ' max size of the upload (KB) note: this doesn't override any server upload limits
    Dim sFileName = ""
dim fileExt	' used to store the file extension (saves finding it mulitple times)
dim newWidth, newHeight as integer ' new width/height for the thumbnail
dim l2	' temp variable used when calculating new size
dim fileFld as HTTPPostedFile	' used to grab the file upload from the form
Dim originalimg As System.Drawing.Image	' used to hold the original image
dim msg	' display results
dim upload_ok as boolean	' did the upload work ?
randomize() ' used to help the cache-busting on the preview images
upload_ok = false
if lcase(Request.ServerVariables("REQUEST_METHOD"))="post" then
        fileFld = Request.Files(0)  ' get the first file uploaded from the form (note:- you can use this to itterate through more than one image)
        upload_original = fileFld.FileName
        sFileName = Left(upload_original, Len(upload_original) - 4)

	if fileFld.ContentLength > upload_max_size * 1024 then
		msg = "Sorry, the image must be less than " & upload_max_size & "Kb"
			originalImg = System.Drawing.Image.FromStream(fileFld.InputStream)
			' work out the width/height for the thumbnail. Preserve aspect ratio and honour max width/height
			' Note: if the original is smaller than the thumbnail size it will be scaled up
			If (originalImg.Width/Lx) > (originalImg.Width/Ly) Then
				L2 = originalImg.Width
				newWidth = Lx
				newHeight = originalImg.Height * (Lx / L2)
				if newHeight > Ly then
					newWidth = newWidth * (Ly / newHeight)
					newHeight = Ly
				end if
				L2 = originalImg.Height
				newHeight = Ly
				newWidth = originalImg.Width * (Ly / L2)
				if newWidth > Lx then
					newHeight = newHeight * (Lx / newWidth)
					newWidth = Lx
				end if
			End If

            Dim thumb As New Bitmap(newWidth, newHeight)

            'Create a graphics object           
            Dim gr_dest As Graphics = Graphics.FromImage(thumb)

			' just in case it's a transparent GIF force the bg to white 
			dim sb = new SolidBrush(System.Drawing.Color.White)
			gr_dest.FillRectangle(sb, 0, 0, thumb.Width, thumb.Height)

            'Re-draw the image to the specified height and width
			gr_dest.DrawImage(originalImg, 0, 0, thumb.Width, thumb.Height)

				fileExt = System.IO.Path.GetExtension(fileFld.FileName).ToLower()
                    originalimg.Save(Server.MapPath(upload_dir & sFileName & fileExt), originalimg.RawFormat)
                    thumb.Save(Server.MapPath(upload_dir & sFileName & upload_thumb & fileExt), originalimg.RawFormat)
                    msg = "Uploaded " & fileFld.FileName & " to " & Server.MapPath(upload_dir & sFileName & fileExt)
				upload_ok = true
				msg = "Sorry, there was a problem saving the image."
			end try
			' Housekeeping for the generated thumbnail
			if not thumb is nothing then
				thumb = nothing
			end if
			msg = "Sorry, that was not an image we could process."
		end try
	end if

	' House Keeping !
	if not originalImg is nothing then
		originalImg = nothing
	end if

end if
<title>ASP.NET File Upload and Resize Sample</title>
<META NAME="Description" CONTENT="ASP.NET File Upload and Resize Sample (Hybrid VB.NET)">
<META NAME="Keywords" CONTENT="ASP.NET, ASP, NET, VB, VBScript, Image, Upload, Resize, Thumbnail, Constrain, Filesize, File, Size, Free">
<META NAME="Copyright" CONTENT="Rufan-Redi Pty Ltd 2005">
<META NAME="Author" CONTENT="System developed by Jeremy at">
    <style type="text/css">
        .style1 {
            width: 144px;

<form id="Form1" enctype="multipart/form-data" method="post" runat="server">
<tr><td class="style1">Select the file to upload:</td><td>
    <input type="file" name="upload_file" 
        id="upload_file" title="upload_file"></td></tr>
<tr><td colspan=2>Max upload size <%=upload_max_size%>Kb, gif/jpg/png only</td></tr>
<tr><td colspan=2><input type="submit" value="Upload"></td></tr>

if upload_ok then
<td valign=top><img src="<%=upload_dir & sFileName & fileExt & "?" & rnd()%>"></td>
<td valign=top><img src="<%=upload_dir & sFileName & upload_thumb & fileExt & "?" & rnd()%>"></td>
end if


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Initial Description

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ASP.NET VB Image Upload and Resize

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