Thread: Create thumbnails dynamically in Vb.net

I am new in this forum. I have one problem with my Vb.net example. I want to create thumbnails dynamically in Vb.net .how it is possible. Please give me step by step code which easy to understand me. Your help highly appericated.

I suggest you to refer following example, which will give you something idea about the use code to Create thumbnails dynamically:

Code:

    Function CreateThumbnail(ByVal inSourceFile As String, ByVal inDestinationFile As String, ByVal ThumbWidth As Integer, ByVal ThumbHeight As Integer) As Boolean
     
        Dim imageFile As System.Drawing.Image
        Dim outputFstream As New FileStream(inSourceFile, FileMode.Open, FileAccess.Read) 
        Dim ImageAbortCallBack As System.Drawing.Image.GetThumbnailImageAbort 
        imageFile = System.Drawing.Image.FromStream(outputFstream)
        ImageAbortCallBack = New System.Drawing.Image.GetThumbnailImageAbort(AddressOf             ImageAbortDummyCallback)
        imageFile = imageFile.GetThumbnailImage(ThumbWidth, ThumbHeight, ImageAbortCallBack, IntPtr.Zero) 
        'IntPtr = A platform-specific type that is used to represent a pointer or a handle.
        imageFile.Save(inDestinationFile, System.Drawing.Imaging.ImageFormat.Jpeg)
        outputFstream.Close()
        outputFstream = Nothing
        imageFile = Nothing

    End Function

Try this,

Code:

 Private Sub btnOpen_Click(ByVal sender As Object, ByVal e As EventArgs)
                  If openFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
                        txtFileNm.Text = openFileDialog1.FileName
                  End If
            End Sub
 Private Sub btnOpen_Click(ByVal sender As Object, ByVal e As EventArgs)
                  If openFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
                        txtFileNm.Text = openFileDialog1.FileName
                  End If
            End Sub
Dim imgThumb As Image = Nothing
            Private Sub btnGenerateThumbnail_Click(ByVal sender As Object, ByVal e As EventArgs)
                  Try
                        Dim image As Image = Nothing
                        ' Check if textbox has a value
                        If txtFileNm.Text <> String.Empty Then
                              image = Image.FromFile(txtFileNm.Text)
                        End If
                        ' Check if image exists
                        If Not image Is Nothing Then
                              imgThumb = image.GetThumbnailImage(100, 100, Nothing, New IntPtr())
                              Me.Refresh()
                        End If
                  Catch
                        MessageBox.Show("An error occured")
                  End Try
            End Sub

Private Sub Form1_Paint(ByVal sender As Object, ByVal e As PaintEventArgs)
                  If Not imgThumb Is Nothing Then
                  e.Graphics.DrawImage(imgThumb,30, 20, imgThumb.Width, imgThumb.Height)
                  End If
            End Sub