how to read image stream?

Question

User1087005990 posted

Dear all here is my code, 

 i want to display thumbnail in my image box, its working fine, but for this i have to save thumbnail first

is it possible that without saving thumbnail i use it?

Private Sub makeThumb(ByVal thumbWidth As Int32, ByVal thumbHight As Int32, ByVal img As String, ByVal thumbName As String)
        'Dim thumbHight As Int32 = h
        'Dim thumbWidth As Int32 = w
        Dim fullImg As String = img
        'Dim thumbName As String
        Dim img1 As System.Drawing.Image
        Dim thumbStream As New System.IO.MemoryStream
        ' Todo

        Try
            img1 = System.Drawing.Image.FromFile(Server.MapPath(fullImg))
            Dim dummyCallBack As System.Drawing.Image.GetThumbnailImageAbort
            dummyCallBack = New System.Drawing.Image.GetThumbnailImageAbort(AddressOf ThumbnailCallback)
            Dim thumbImg As System.Drawing.Image
            thumbImg = img1.GetThumbnailImage(thumbWidth, thumbHight, dummyCallBack, IntPtr.Zero)
            thumbImg.Save(thumbStream, System.Drawing.Imaging.ImageFormat.Jpeg)
            MsgBox(thumbStream.Length)

            'thumbImg.Save(Server.MapPath("images/" & thumbName), ImageFormat.Jpeg)
            'imgThumb.ImageUrl = "images\smallReal.jpeg"
        Catch ex As Exception
            Response.Write("there is some problem in code <br />" & ex.ToString)
        End Try
    End Sub 

 

 Private Sub makeThumb(ByVal thumbWidth As Int32, ByVal thumbHight As Int32, ByVal img As String, ByVal thumbName As String)
     
        Dim fullImg As String = img
     
        Dim img1 As System.Drawing.Image

     
        Try
            img1 = System.Drawing.Image.FromFile(Server.MapPath(fullImg))
            Dim dummyCallBack As System.Drawing.Image.GetThumbnailImageAbort
            dummyCallBack = New System.Drawing.Image.GetThumbnailImageAbort(AddressOf ThumbnailCallback)
            Dim thumbImg As System.Drawing.Image
            thumbImg = img1.GetThumbnailImage(thumbWidth, thumbHight, dummyCallBack, IntPtr.Zero)
               
           thumbImg.Save(Server.MapPath("images/" & thumbName), ImageFormat.Jpeg)
           imgThumb.ImageUrl = "images\smallReal.jpeg"
        Catch ex As Exception
            Response.Write("there is some problem in code <br />" & ex.ToString)
        End Try
    End Sub

 

thanks

 

Answer 1

User1742304165 posted

This is very easy to do.  Use a handler send it back to the browser. 

http://www.codeproject.com/KB/web-image/thumbnailer.aspx?display=Print

if you need some help, let me know.  that should explain it, if not i, have a code sample for you somewhere.

Joshua