VintaSoft Imaging .NET SDK 11.0
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    PDF: Edit content of PDF page programmatically
    In This Topic

    The SDK has algorithm that divides all content (graphics, images, forms, text, clip region) on PDF page into graphical figures.

    The PdfContentGraphicsFigureEditor class allows to edit graphical figures of PDF page programmatically.
    The editor allows to do the following operations:


    Here is an example that demonstrates how to change the location of specified resource on PDF page:
    ' The project, which uses this code, must have references to the following assemblies:
    ' - Vintasoft.Imaging
    ' - Vintasoft.Imaging.Pdf
    
    ''' <summary>
    ''' Sets the resource location on PDF page.
    ''' </summary>
    ''' <param name="inPdfFilename">The filename of input PDF document.</param>
    ''' <param name="outPdfFilename">The filename of output PDF document.</param>
    ''' <param name="pageIndex">Index of the PDF page.</param>
    ''' <param name="resourceIndex">Index of the resource on PDF page.</param>
    ''' <param name="newLocation">The new location in PDF page space.</param>
    Public Shared Sub SetResourceLocation(inPdfFilename As String, outPdfFilename As String, pageIndex As Integer, resourceIndex As Integer, newLocation As System.Drawing.PointF)
        ' open PDF document
        Using document As New Vintasoft.Imaging.Pdf.PdfDocument(inPdfFilename)
            ' create PdfContentGraphicsFigureEditor on specified PDF page
            Using contentEditor As New Vintasoft.Imaging.Pdf.Content.PdfContentGraphicsFigureEditor(document.Pages(pageIndex), False)
                Dim currentResourceIndex As Integer = 0
                ' for each graphics figure on PDF page
                For Each figure As Vintasoft.Imaging.Pdf.Drawing.GraphicsFigures.ContentStreamGraphicsFigure In contentEditor.GraphicsFigures
                    ' if graphics figure has resource
                    If figure.Resource IsNot Nothing Then
                        ' if this is graphics figure that should be changed
                        If currentResourceIndex = resourceIndex Then
                            ' get the bounding box of graphics figure
                            Dim resourceBBox As System.Drawing.RectangleF = figure.GetRegion().Bounds
                            ' create transformation that changes coordinates of object
                            Dim transform As Vintasoft.Imaging.AffineMatrix = Vintasoft.Imaging.AffineMatrix.CreateTranslation(newLocation.X - resourceBBox.X, newLocation.Y - resourceBBox.Y)
                            ' apply transformation to the graphics figure
                            contentEditor.Transform(figure, transform)
                            Exit For
                        End If
    
                        currentResourceIndex += 1
                    End If
                Next
                If currentResourceIndex <> resourceIndex Then
                    Throw New System.IndexOutOfRangeException(String.Format("Resource with index {0} was not found", resourceIndex))
                End If
            End Using
    
            ' save PDF document to a new file
            document.Save(outPdfFilename)
        End Using
    End Sub
    
    // The project, which uses this code, must have references to the following assemblies:
    // - Vintasoft.Imaging
    // - Vintasoft.Imaging.Pdf
    
    /// <summary>
    /// Sets the resource location on PDF page.
    /// </summary>
    /// <param name="inPdfFilename">The filename of input PDF document.</param>
    /// <param name="outPdfFilename">The filename of output PDF document.</param>
    /// <param name="pageIndex">Index of the PDF page.</param>
    /// <param name="resourceIndex">Index of the resource on PDF page.</param>
    /// <param name="newLocation">The new location in PDF page space.</param>
    public static void SetResourceLocation(string inPdfFilename, string outPdfFilename, int pageIndex, int resourceIndex, System.Drawing.PointF newLocation)
    {
        // open PDF document
        using (Vintasoft.Imaging.Pdf.PdfDocument document = new Vintasoft.Imaging.Pdf.PdfDocument(inPdfFilename))
        {
            // create PdfContentGraphicsFigureEditor on specified PDF page
            using (Vintasoft.Imaging.Pdf.Content.PdfContentGraphicsFigureEditor contentEditor =
                new Vintasoft.Imaging.Pdf.Content.PdfContentGraphicsFigureEditor(document.Pages[pageIndex], false))
            {
                int currentResourceIndex = 0;
                // for each graphics figure on PDF page
                foreach (Vintasoft.Imaging.Pdf.Drawing.GraphicsFigures.ContentStreamGraphicsFigure figure in contentEditor.GraphicsFigures)
                {
                    // if graphics figure has resource
                    if (figure.Resource != null)
                    {
                        // if this is graphics figure that should be changed
                        if (currentResourceIndex == resourceIndex)
                        {
                            // get the bounding box of graphics figure
                            System.Drawing.RectangleF resourceBBox = figure.GetRegion().Bounds;
                            // create transformation that changes coordinates of object
                            Vintasoft.Imaging.AffineMatrix transform = Vintasoft.Imaging.AffineMatrix.CreateTranslation(newLocation.X - resourceBBox.X, newLocation.Y - resourceBBox.Y);
                            // apply transformation to the graphics figure
                            contentEditor.Transform(figure, transform);
                            break;
                        }
    
                        currentResourceIndex++;
                    }
                }
                if (currentResourceIndex != resourceIndex)
                    throw new System.IndexOutOfRangeException(string.Format("Resource with index {0} was not found", resourceIndex));
            }
            
            // save PDF document to a new file
            document.Save(outPdfFilename);
        }
    }