PDF: Edit content of PDF page programmatically
 
            
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            		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 C#/VB.NET code that demonstrates how to change the location of specified resource on PDF page:
		
		
    
	
	    
	    
/// <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);
    }
}
	     
	 
 
    
	
	    
	    
''' <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