VisitSmartTagStart

DocumentVisitor.VisitSmartTagStart method

Called when enumeration of a smart tag has started.

public virtual VisitorAction VisitSmartTagStart(SmartTag smartTag)
ParameterTypeDescription
smartTagSmartTagThe object that is being visited.

Return Value

A VisitorAction value that specifies how to continue the enumeration.

Examples

Shows how to print the node structure of every smart tag in a document.

public void SmartTagToText()
{
    Document doc = new Document(MyDir + "Smart tags.doc");
    SmartTagStructurePrinter visitor = new SmartTagStructurePrinter();

    // When we get a composite node to accept a document visitor, the visitor visits the accepting node,
    // and then traverses all the node's children in a depth-first manner.
    // The visitor can read and modify each visited node.
    doc.Accept(visitor);

    Console.WriteLine(visitor.GetText());
}

/// <summary>
/// Traverses a node's non-binary tree of child nodes.
/// Creates a map in the form of a string of all encountered SmartTag nodes and their children.
/// </summary>
public class SmartTagStructurePrinter : DocumentVisitor
{
    public SmartTagStructurePrinter()
    {
        mBuilder = new StringBuilder();
        mVisitorIsInsideSmartTag = false;
    }

    /// <summary>
    /// Gets the plain text of the document that was accumulated by the visitor.
    /// </summary>
    public string GetText()
    {
        return mBuilder.ToString();
    }

    /// <summary>
    /// Called when a Run node is encountered in the document.
    /// </summary>
    public override VisitorAction VisitRun(Run run)
    {
        if (mVisitorIsInsideSmartTag) IndentAndAppendLine("[Run] \"" + run.GetText() + "\"");

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a SmartTag node is encountered in the document.
    /// </summary>
    public override VisitorAction VisitSmartTagStart(SmartTag smartTag)
    {
        IndentAndAppendLine("[SmartTag start] Name: " + smartTag.Element);
        mDocTraversalDepth++;
        mVisitorIsInsideSmartTag = true;

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called after all the child nodes of a SmartTag node have been visited.
    /// </summary>
    public override VisitorAction VisitSmartTagEnd(SmartTag smartTag)
    {
        mDocTraversalDepth--;
        IndentAndAppendLine("[SmartTag end]");
        mVisitorIsInsideSmartTag = false;

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Append a line to the StringBuilder and indent it depending on how deep the visitor is into the document tree.
    /// </summary>
    /// <param name="text"></param>
    private void IndentAndAppendLine(string text)
    {
        for (int i = 0; i < mDocTraversalDepth; i++) mBuilder.Append("|  ");

        mBuilder.AppendLine(text);
    }

    private bool mVisitorIsInsideSmartTag;
    private int mDocTraversalDepth;
    private readonly StringBuilder mBuilder;
}

See Also