CGContext.DrawPDFPage(CGPDFPage) 方法

定义

命名空间:

CoreGraphics

程序集:

Xamarin.iOS.dll

呈现指定的 PDF page。

public void DrawPDFPage (CoreGraphics.CGPDFPage page);

member this.DrawPDFPage : CoreGraphics.CGPDFPage -> unit

参数

page

CGPDFPage

要呈现的 PDF 页面。

注解

以下示例演示如何呈现 PDF 文件的第一页：

doc = CGPDFDocument.FromFile (Path.Combine (NSBundle.MainBundle.BundlePath, "Images/QuartzImageDrawing.pdf"));
if (doc == null)
		throw new Exception ("Could not load document");

using (var ctxt = UIGraphics.GetCurrentContext ()) {
  // PDF page drawing expects a Lower-Left coordinate system, so we flip the coordinate system
	// before we start drawing.
	context.TranslateCTM (0, Bounds.Height);
	context.ScaleCTM (1, -1);

	// Grab the first PDF page
	using (CGPDFPage page = doc.GetPage (1)){
		// We're about to modify the context CTM to draw the PDF page where we want it, so save the graphics state in case we want to do more drawing
		context.SaveState ();

		// CGPDFPageGetDrawingTransform provides an easy way to get the transform for a PDF page. It will scale down to fit, including any
		// base rotations necessary to display the PDF page correctly.

		CGAffineTransform pdfTransform = page.GetDrawingTransform (CGPDFBox.Crop, Bounds, 0, true);

		// And apply the transform.
		context.ConcatCTM (pdfTransform);
		// Finally, we draw the page and restore the graphics state for further manipulations!
		context.DrawPDFPage (page);
		context.RestoreState();
	}				
}