Writing text on the middle of a page of an existing PDF

[Loïc]

Code: Select all

        Dim oGdPicturePDF As New GdPicture.GdPicturePDF
        Dim text As String = "Hello World!"
        Dim textSize As Single = 12
        oGdPicturePDF.LoadFromFile("c:\TWAIN_2_1_Spec.pdf", False)
        Dim pageWidth As Single = oGdPicturePDF.GetPageWidth 'Be careful: this function returns value in PDF points unit
        Dim pageHeight As Single = oGdPicturePDF.GetPageHeight 'Be careful: this function returns value in PDF points unit
        Dim fontResName As String = oGdPicturePDF.AddTrueTypeFont("Arial", False, False, False)
        oGdPicturePDF.SelectPage(1)
        oGdPicturePDF.SetMeasurementUnit(PdfMeasurementUnit.PdfMeasurementUnitPoint)
        oGdPicturePDF.SetOrigin(PdfOrigin.PdfOriginTopLeft)
        oGdPicturePDF.SetTextSize(textSize)
        Dim textWidth As Single = oGdPicturePDF.GetTextWidth(fontResName, textSize, text)
        oGdPicturePDF.DrawText(fontResName, pageWidth / 2 - textWidth / 2, pageHeight / 2, text)
        oGdPicturePDF.SaveToFileInc("c:\newpdf.pdf")
        oGdPicturePDF.CloseDocument()