Add a rectangle annotation to a PDF in UWP

1PDFDoc doc = new PDFDoc(filename);
2Page page = doc.GetPage(1);
3
4// Create a rectangle
5Square sq = Square.Create( doc, new Rect(500,200, 580, 300 ) );
6sq.SetColor(new ColorPt(1, 0, 0), 3);
7sq.SetInteriorColor(new ColorPt(0, 1, 1), 3);
8double[] dash = new double[2];
9dash[0]=4;dash[1]=2;
10sq.SetBorderStyle(new Annot.BorderStyle( Annot.BorderStyle.Style.e_dashed, 6, 0, 0, dash ) );
11sq.SetPadding( new Rect(4,4,4,4) );
12sq.RefreshAppearance();
13page.AnnotPushBack( sq );