public static void RenderNode(Node node, string filePath, ImageSaveOptions imageOptions)
{
// Run some argument checks.
if (node == null)
throw new ArgumentException("Node cannot be null");
// If no image options are supplied, create default options.
if (imageOptions == null)
imageOptions = new ImageSaveOptions(FileFormatUtil.ExtensionToSaveFormat(Path.GetExtension(filePath)));
// Store the paper color to be used on the final image and change to transparent.
// This will cause any content around the rendered node to be removed later on.
Color savePaperColor = imageOptions.PaperColor;
imageOptions.PaperColor = Color.Transparent;
// There a bug which affects the cache of a cloned node. To avoid this we instead clone the entire document including all nodes,
// find the matching node in the cloned document and render that instead.
Document doc = (Document)node.Document.Clone(true);
node = doc.GetChild(NodeType.Any, node.Document.GetChildNodes(NodeType.Any, true).IndexOf(node), true);
// Create a temporary shape to store the target node in. This shape will be rendered to retrieve
// the rendered content of the node.
Shape shape = new Shape(doc, ShapeType.TextBox);
Section parentSection = (Section)node.GetAncestor(NodeType.Section);
// Assume that the node cannot be larger than the page in size.
shape.Width = parentSection.PageSetup.PageWidth;
shape.Height = parentSection.PageSetup.PageHeight;
shape.FillColor = Color.Transparent; // We must make the shape and paper color transparent.
// Don't draw a surronding line on the shape.
shape.Stroked = false;
// Move up through the DOM until we find node which is suitable to insert into a Shape (a node with a parent can contain paragraph, tables the same as a shape).
// Each parent node is cloned on the way up so even a descendant node passed to this method can be rendered.
// Since we are working with the actual nodes of the document we need to clone the target node into the temporary shape.
Node currentNode = node;
while (!(currentNode.ParentNode is InlineStory || currentNode.ParentNode is Story || currentNode.ParentNode is ShapeBase))
{
CompositeNode parent = (CompositeNode)currentNode.ParentNode.Clone(false);
currentNode = currentNode.ParentNode;
parent.AppendChild(node.Clone(true));
node = parent; // Store this new node to be inserted into the shape.
}
// We must add the shape to the document tree to have it rendered.
shape.AppendChild(node.Clone(true));
parentSection.Body.FirstParagraph.AppendChild(shape);
// Render the shape to stream so we can take advantage of the effects of the ImageSaveOptions class.
// Retrieve the rendered image and remove the shape from the document.
MemoryStream stream = new MemoryStream();
shape.GetShapeRenderer().Save(stream, imageOptions);
shape.Remove();
// Load the image into a new bitmap.
using (Bitmap renderedImage = new Bitmap(stream))
{
// Extract the actual content of the image by cropping transparent space around
// the rendered shape.
Rectangle cropRectangle = FindBoundingBoxAroundNode(renderedImage);
Bitmap croppedImage = new Bitmap(cropRectangle.Width, cropRectangle.Height);
croppedImage.SetResolution(imageOptions.Resolution, imageOptions.Resolution);
// Create the final image with the proper background color.
using (Graphics g = Graphics.FromImage(croppedImage))
{
g.Clear(savePaperColor);
g.DrawImage(renderedImage, new Rectangle(0, 0, croppedImage.Width, croppedImage.Height), cropRectangle.X, cropRectangle.Y, cropRectangle.Width, cropRectangle.Height, GraphicsUnit.Pixel);
croppedImage.Save(filePath);
}
}
}