<%@ Page Language="C#" EnableSessionState="False" EnableViewState="False"%>
<%@ Import Namespace="System.IO"%>
<%@ Import Namespace="System.Drawing"%>
<%@ Import Namespace="System.Drawing.Imaging"%>
<%@ Import Namespace="System.Text.RegularExpressions"%>
<Script runat="server">
/*
Original concept and VB.Net code by Stephen Gilboy
http://www.morningz.com/mz/crystal/dotnet/uploadImage.aspx

C# Interpretation by Graham G. Elliott
http://www.goucham.net/net/uploadImage.aspx

sVirtualPath   -> Location of virtual path, used to later display
sPath          -> Location of save path, make sure its a dir where ASPNET has FULL rights
sOverlayText   -> Will be overlayed on top left of image, leave empty to not overlay
iMaxWidth      -> Max width of the uploaded image, set to 0 to not resize
iMaxThumbWidth -> Max width of generated thumbnail, set to 0 to not make thumbnail
*/
 const String sVirtualPath = "/tmp/";
 const String sOverlayText = ".NET Rules!!";
 const int iMaxWidth = 550;
 const int iMaxThumbWidth = 75;
 String sPath = HttpContext.Current.Server.MapPath(sVirtualPath);

 void Upload_Click(Object sender, EventArgs e)
 {
   if (uploadedFile.PostedFile != null) Process_Upload();
 }

 void Process_Upload()
 {
   try 
   {
    //Check for common errors.
     if (!Check_Upload(uploadedFile.PostedFile)) return;

    //Initializing local variables
     HttpPostedFile myUpload = uploadedFile.PostedFile;
     int myLength = myUpload.ContentLength;
     String myType = myUpload.ContentType;
     String myName = Path.GetFileName(myUpload.FileName);

     message.Text = "<b>Accepted Upload:</b> " + myName + "<br>" +
                    "<b>Content Type:</b> " + myType + "<br>" +
                    "<b>File Size:</b> " + myLength.ToString() + "<br>";

    //Running main image processing routine
     Process_Image(myUpload.InputStream, Path.ChangeExtension(myName, ".jpg"));
   }
   catch (Exception exc)
   {
     message.Text = "<b>Upload Failed:</b> " + exc.ToString();
   }
 }
 
 void Process_Image(Stream myStream, String myName)
 {
  //Initializing local variables
   System.Drawing.Image myImage = System.Drawing.Image.FromStream(myStream);
   String myPath = Path.Combine(sPath, myName);
   String myThumbPath = Path.Combine(sPath, "tn_" + myName);
   int oldWidth = myImage.Width;
   int oldHeight = myImage.Height;
   int newWidth;
   int newHeight;

   message.Text += "<b>Dimensions:</b> " + oldWidth + " x " + oldHeight + "<br>";

  //Determining new image size
   if ((iMaxWidth > 0) && (oldWidth > iMaxWidth))
   {
     newWidth = iMaxWidth;
     newHeight = (int) (oldHeight / ((Double) oldWidth / newWidth));
     message.Text += "<b>Image re-sized to:</b> " + newWidth + " x " + newHeight + "<br>";
   }else{
     newWidth = oldWidth;
     newHeight = oldHeight;
   }

  //Creating new, re-sized image
   Bitmap myBitmap = new Bitmap(myImage, newWidth, newHeight);

  //Creating the text overlay for re-sized image
   if (sOverlayText != "")
   {
     Graphics myCanvas = Graphics.FromImage(myBitmap);
     Font myFont = new Font("Verdana", 10, FontStyle.Bold);
     StringFormat myFormat = new StringFormat(StringFormatFlags.LineLimit);

     myCanvas.DrawString(sOverlayText, myFont, Brushes.Black, new PointF(4, 4), myFormat);
     myCanvas.DrawString(sOverlayText, myFont, Brushes.Black, new PointF(6, 6), myFormat);
     myCanvas.DrawString(sOverlayText, myFont, Brushes.Black, new PointF(4, 6), myFormat);
     myCanvas.DrawString(sOverlayText, myFont, Brushes.Black, new PointF(6, 4), myFormat);
     myCanvas.DrawString(sOverlayText, myFont, Brushes.Yellow, new PointF(5, 5), myFormat);
     myCanvas.Dispose();

     message.Text += "<b>Text Added:</b> " + sOverlayText + "<br>";
   }

  //Writing text overlayed image to disk and cleaning up
   myBitmap.Save(myPath, ImageFormat.Jpeg);
   myBitmap.Dispose();

   message.Text += "<b>File Saved As:</b> " + myPath + "<br>";
   image.Src = sVirtualPath + myName;
   image.Visible = true;

  //Creating thumbnail and writing to disk
   if (iMaxThumbWidth > 0)
   {
     Bitmap myThumb = new Bitmap(myImage, iMaxThumbWidth, (int) (newHeight / ((Double) newWidth / iMaxThumbWidth)));
     myThumb.Save(myThumbPath, ImageFormat.Jpeg);
     myThumb.Dispose();

     message.Text += "<b>Thumbnail Saved As:</b> " + myThumbPath + "<br>";
     thumb.Src = sVirtualPath + "tn_" + myName;
     thumb.Visible = true;
   }

  //Cleaning up parent image object
   myImage.Dispose();
 }

 bool Check_Upload(HttpPostedFile fileUpped)
 {
  //Checking to see if field was left empty
   if (fileUpped.FileName == "")
   {
     message.Text = "<b>Upload Failed:</b> No file sbumitted";
     return false;
   }
  //Checking for Jpeg / Gif mime types
   if (!Regex.IsMatch(fileUpped.ContentType, "image/(?:\\w?jpeg|gif|png)", RegexOptions.IgnoreCase))
   {
     message.Text = "<b>Upload Failed:</b> Only JPG's and GIF's allowed";
     return false;
   }
  //Checking for zero length.  You could also use to check for large files.
   if (fileUpped.ContentLength == 0)
   {
     message.Text = "<b>Upload Failed:</b> File cannot be zero bytes.";
     return false;
   }

   return true;
 }
</Script>
<html>
<head>
<title>Upload and Resize an Image</title>
</head>
<body bgcolor="white" style="font-family: Verdana; font-size: 8 pt;">
<h2>Parameters:</h2>
<li><b>File Types Accepted:</b> GIF, PNG and JPG's Accepted</li>
<li><b>Current Save Path:</b> <%=sPath %></li>
<li><b>Images will be Saved As:</b> JPG Format</li>
<li><b>Current Max Width:</b> <%=iMaxWidth%></li>
<li><b>Current Thumbnail Width:</b> <%=iMaxThumbWidth%></li>
<li><b>Current Overlay Text:</b> <%=sOverlayText%></li>
<br/>
<form enctype="multipart/form-data" runat="server">
 Select File to Upload:
 <input id="uploadedFile" type="file" runat="server"/>
 <p><input id="upload" type="button" value="Upload" onserverclick="Upload_Click" runat="server"/></p>
 <p><asp:Label id="message" runat="server"/></p>
 <img id="image" visible="false" runat="server"/>
 <br>
 <img id="thumb" visible="false" runat="server"/>
</form>
</body>
</html>