Add Line Object to PDF file

Add Line object

Aspose.PDF for C++ supports the feature to add graph objects (for example graph, line, rectangle etc.) to PDF documents. You also get the leverage to add Line object where you can also specify the dash pattern, color and other formatting for Line element.

Follow the steps below:

1. Create a new PDF Document

2. Add Page to pages collection of PDF file

3. Create Graph instance.

4. Add Graph object to paragraphs collection of page instance.

5. Create Rectangle instance.

6. Set line width.

7. Add Rectangle object to shapes collection of Graph object.

8. Save your PDF file.

The following code snippet shows how to add a Rectangle object that is filled with color.

 
void AddLineObjectToPDF()
{
	String _dataDir("C:\\Samples\\");
	// Create Document instance
	auto document = MakeObject<Document>();

	// Add page to pages collection of PDF file
	auto page = document->get_Pages()->Add();

	// Create Graph instance
	auto graph = MakeObject<Aspose::Pdf::Drawing::Graph>(100, 400);

	// Add graph object to paragraphs collection of page instance
	page->get_Paragraphs()->Add(graph);

	// Create Rectangle instance
	auto line = MakeObject<Aspose::Pdf::Drawing::Line>(new float[] { 100, 100, 200, 100 });
	
	// Specify fill color for Graph object
	line->get_GraphInfo()->set_DashArray (MakeArray<int>({ 0, 1, 0 }));
	line->get_GraphInfo()->set_DashPhase (1);
	
	// Add rectangle object to shapes collection of Graph object
	graph->get_Shapes()->Add(line);
	
	// Save PDF file
	document->Save(_dataDir + u"AddLineObject_out.pdf");
}

How to add Dotted Dashed Line to your PDF document

void DashLengthInBlackAndDashLengthInWhite()
{
	String _dataDir("C:\\Samples\\");
	// Create Document instance
	auto document = MakeObject<Document>();

	// Add page to pages collection of PDF file
	auto page = document->get_Pages()->Add();

	// Create Drawing object with certain dimensions
	auto canvas = MakeObject<Aspose::Pdf::Drawing::Graph>(100, 400);
	// Add drawing object to paragraphs collection of page instance
	page->get_Paragraphs()->Add(canvas);
	
	// Create Line object
	auto line = MakeObject<Aspose::Pdf::Drawing::Line>(MakeArray<float>({ 100, 100, 200, 100 }));
	// Set color for Line object
	line->get_GraphInfo()->set_Color (Aspose::Pdf::Color::get_Red());
	// Specify dash array for line object
	line->get_GraphInfo()->set_DashArray(MakeArray<int>({ 0, 1, 0 }));
	// Set the dash phase for Line instance
	line->get_GraphInfo()->set_DashPhase(1);
	// Add line to shapes collection of drawing object
	canvas->get_Shapes()->Add(line);	
	// Save PDF file
	document->Save(_dataDir + u"DashLength_out.pdf");
}

Let’s check the result:

Draw Line Across the Page

We can also use line object to draw a cross starting from Left-Bottom to Right-Upper corner and Left-Top corner to Bottom-Right corner.

Please take a look over following code snippet to accomplish this requirement.

void ExampleLineAcrossPage() {

    // Create Document instance
    String _dataDir("C:\\Samples\\");
    // Create Document instance
    auto document = MakeObject<Document>();
   
    // Add page to pages collection of PDF file
    auto page = document->get_Pages()->Add();
    // Set page margin on all sides as 0

    page->get_PageInfo()->get_Margin()->set_Left(0);
    page->get_PageInfo()->get_Margin()->set_Right(0);
    page->get_PageInfo()->get_Margin()->set_Bottom(0);
    page->get_PageInfo()->get_Margin()->set_Top(0);

    // Create Graph object with Width and Height equal to page dimensions
    auto graph = MakeObject<Aspose::Pdf::Drawing::Graph>(
        page->get_PageInfo()->get_Width(), 
        page->get_PageInfo()->get_Height());

    // Create first line object starting from Lower-Left to Top-Right corner of page
    auto line = MakeObject<Aspose::Pdf::Drawing::Line>(
        MakeArray<double>({ 
                      page->get_Rect()->get_LLX(), 0, 
                      page->get_PageInfo()->get_Width(),
                      page->get_Rect()->get_URY() }));

    // Add line to shapes collection of Graph object
    graph->get_Shapes()->Add(line);
    // Draw line from Top-Left corner of page to Bottom-Right corner of page
    auto line2 = MakeObject<Aspose::Pdf::Drawing::Line>( MakeArray<double>({0, 
        page->get_Rect()->get_URY(), page->get_PageInfo()->get_Width(), page->get_Rect()->get_LLX() }));

    // Add line to shapes collection of Graph object
    graph->get_Shapes()->Add(line2);
    // Add Graph object to paragraphs collection of page
    page->get_Paragraphs()->Add(graph);

    // Save PDF file
    document->Save(_dataDir + u"DrawingLine_out.pdf");
}