NodeImporter Class

Allows to efficiently perform repeated import of nodes from one document to another.
Inheritance Hierarchy
SystemObject
  Aspose.WordsNodeImporter

Namespace:  Aspose.Words
Assembly:  Aspose.Words (in Aspose.Words.dll) Version: 20.3
Syntax
public class NodeImporter

The NodeImporter type exposes the following members.

Constructors
  NameDescription
Public methodCode exampleNodeImporter(DocumentBase, DocumentBase, ImportFormatMode)
Initializes a new instance of the NodeImporter class.
Public methodCode exampleNodeImporter(DocumentBase, DocumentBase, ImportFormatMode, ImportFormatOptions)
Initializes a new instance of the NodeImporter class.
Methods
  NameDescription
Public methodEquals (Inherited from Object.)
Public methodGetHashCode (Inherited from Object.)
Public methodGetType (Inherited from Object.)
Public methodCode exampleImportNode

Imports a node from one document into another.

Public methodToString (Inherited from Object.)
Remarks

Aspose.Words provides functionality for easy copying and moving fragments between Microsoft Word documents. This is known as "importing nodes". Before you can insert a fragment from one document into another, you need to "import" it. Importing creates a deep clone of the original node, ready to be inserted into the destination document.

The simplest way to import a node is to use the ImportNode(Node, Boolean) method provided by the DocumentBase object.

However, when you need to import nodes from one document to another multiple times, it is better to use the NodeImporter class. The NodeImporter class allows to minimize the number of styles and lists created in the destination document.

Copying or moving fragments from one Microsoft Word document to another presents a number of technical challenges for Aspose.Words. In a Word document, styles and list formatting are stored centrally, separately from the text of the document. The paragraphs and runs of text merely reference the styles by internal unique identifiers.

The challenges arise from the fact that styles and lists are different in different documents. For example, to copy a paragraph formatted with the Heading 1 style from one document to another, a number of things must be taken into account: decide whether to copy the Heading 1 style from the source document to the destination document, clone the paragraph, update the cloned paragraph so it refers to the correct Heading 1 style in the destination document. If the style had to be copied, all the styles that it references (based on style and next paragraph style) should be analyzed and possibly copied too and so on. Similar issues exist when copying bulleted or numbered paragraphs because Microsoft Word stores list definitions separately from text.

The NodeImporter class is like a context, that holds the "translation tables" during the import. It correctly translates between styles and lists in the source and destination documents.

Examples
This is a method that inserts contents of one document at a specified location in another document.
/// <summary>
/// Inserts content of the external document after the specified node.
/// Section breaks and section formatting of the inserted document are ignored.
/// </summary>
/// <param name="insertAfterNode">Node in the destination document after which the content 
/// should be inserted. This node should be a block level node (paragraph or table).</param>
/// <param name="srcDoc">The document to insert.</param>
static void InsertDocument(Node insertAfterNode, Document srcDoc)
{
    // Make sure that the node is either a paragraph or table
    if ((!insertAfterNode.NodeType.Equals(NodeType.Paragraph)) &
        (!insertAfterNode.NodeType.Equals(NodeType.Table)))
        throw new ArgumentException("The destination node should be either a paragraph or table.");

    // We will be inserting into the parent of the destination paragraph
    CompositeNode dstStory = insertAfterNode.ParentNode;

    // This object will be translating styles and lists during the import
    NodeImporter importer =
        new NodeImporter(srcDoc, insertAfterNode.Document, ImportFormatMode.KeepSourceFormatting);

    // Loop through all sections in the source document
    foreach (Section srcSection in srcDoc.Sections.OfType<Section>())
    {
        // Loop through all block level nodes (paragraphs and tables) in the body of the section
        foreach (Node srcNode in srcSection.Body)
        {
            // Let's skip the node if it is a last empty paragraph in a section
            if (srcNode.NodeType.Equals(NodeType.Paragraph))
            {
                Paragraph para = (Paragraph) srcNode;
                if (para.IsEndOfSection && !para.HasChildNodes)
                    continue;
            }

            // This creates a clone of the node, suitable for insertion into the destination document
            Node newNode = importer.ImportNode(srcNode, true);

            // Insert new node after the reference node
            dstStory.InsertAfter(newNode, insertAfterNode);
            insertAfterNode = newNode;
        }
    }
}
See Also