Demo of ShowImage.aspx

This demo illustrates using the ASP.NET Web page ShowImage.aspx. The following HTML is used in the demo: 

<img src="/demos/ShowImage.aspx?img=dgeditss.gif" />

Source Code 
Below is the source code for ShowImage.aspx


<%@Import Namespace="System.Drawing.Imaging" %>
<script language="VB" runat="server">
  Sub Page_Load(sender as Object, e as EventArgs)
  
    'Read in the image filename to create a thumbnail of
    Dim imageUrl as String = Request.QueryString("img")
    
    'Make sure that the image URL doesn't contain any /'s or \'s
    If imageUrl.IndexOf("/") >= 0 Or imageUrl.IndexOf("\") >= 0 then
      'We found a / or \
      Response.End()
    End If
    
    'Add on the appropriate directory
    imageUrl = "/images/" & imageUrl
    
    'Get the image.    
    Dim fullSizeImg as System.Drawing.Image
    fullSizeImg = System.Drawing.Image.FromFile(Server.MapPath(imageUrl))
    
    'Set the ContentType to "image/gif" and output the image's data
    Response.ContentType = "image/gif"
    fullSizeImg.Save(Response.OutputStream, ImageFormat.Gif)  
  End Sub
</script>

[Return to the article]