Difference between PdfCanvas and Canvas in itext 7

Question

What is the difference between the PdfCanvas and Canvas classes in the iText7 library? When should I use each one of them?

Answer 1

In a nutshell, PdfCanvas is designed for low-level operations and Canvas - for high-level ones.

You want to write rectangles / pathes / text and any other operators to the content stream of a pdf? Use the PdfCanvas instance.

You want to add high-level iText objects (Paragraphs, Tables, Lists, ...) to your PdfCanvas? Use the Canvas instance.

PdfCanvas example

        PdfDocument pdfDoc = new PdfDocument(new PdfWriter(destinationFolder + "simpleCanvas.pdf"));

    PdfPage page1 = pdfDoc.addNewPage();

    PdfCanvas canvas = new PdfCanvas(page1);
    canvas.rectangle(100, 100, 100, 100).fill();

    pdfDoc.close();

The resultant pdf:

Canvas example

            PdfDocument pdf = new PdfDocument(new PdfWriter(out));

    PdfPage page = pdf.addNewPage();
    PdfCanvas pdfCanvas = new PdfCanvas(page);

    Rectangle rectangle = new Rectangle(100, 100, 100, 100);

    Canvas canvas = new Canvas(pdfCanvas, pdf, rectangle);
    canvas.add(new Paragraph("Hello World"));

    canvas.close();

    pdf.close();

The resultant pdf: