VisitShapeStart

DocumentVisitor.VisitShapeStart method

Called when enumeration of a shape has started.

public virtual VisitorAction VisitShapeStart(Shape shape)
ParameterTypeDescription
shapeShapeThe object that is being visited.

Return Value

A VisitorAction value that specifies how to continue the enumeration.

Examples

Shows how to create a group of shapes, and print its contents using a document visitor.

public void GroupOfShapes()
{
    Document doc = new Document();
    DocumentBuilder builder = new DocumentBuilder(doc);

    // If you need to create "NonPrimitive" shapes, such as SingleCornerSnipped, TopCornersSnipped, DiagonalCornersSnipped,
    // TopCornersOneRoundedOneSnipped, SingleCornerRounded, TopCornersRounded, DiagonalCornersRounded
    // please use DocumentBuilder.InsertShape methods.
    Shape balloon = new Shape(doc, ShapeType.Balloon)
    {
        Width = 200,
        Height = 200,
        Stroke = { Color = Color.Red }
    };

    Shape cube = new Shape(doc, ShapeType.Cube)
    {
        Width = 100,
        Height = 100,
        Stroke = { Color = Color.Blue }
    };

    GroupShape group = new GroupShape(doc);
    group.AppendChild(balloon);
    group.AppendChild(cube);

    Assert.True(group.IsGroup);

    builder.InsertNode(group);

    ShapeGroupPrinter printer = new ShapeGroupPrinter();
    group.Accept(printer);

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

/// <summary>
/// Prints the contents of a visited shape group to the console.
/// </summary>
public class ShapeGroupPrinter : DocumentVisitor
{
    public ShapeGroupPrinter()
    {
        mBuilder = new StringBuilder();
    }

    public string GetText()
    {
        return mBuilder.ToString();
    }

    public override VisitorAction VisitGroupShapeStart(GroupShape groupShape)
    {
        mBuilder.AppendLine("Shape group started:");
        return VisitorAction.Continue;
    }

    public override VisitorAction VisitGroupShapeEnd(GroupShape groupShape)
    {
        mBuilder.AppendLine("End of shape group");
        return VisitorAction.Continue;
    }

    public override VisitorAction VisitShapeStart(Shape shape)
    {
        mBuilder.AppendLine("\tShape - " + shape.ShapeType + ":");
        mBuilder.AppendLine("\t\tWidth: " + shape.Width);
        mBuilder.AppendLine("\t\tHeight: " + shape.Height);
        mBuilder.AppendLine("\t\tStroke color: " + shape.Stroke.Color);
        mBuilder.AppendLine("\t\tFill color: " + shape.Fill.ForeColor);
        return VisitorAction.Continue;
    }

    public override VisitorAction VisitShapeEnd(Shape shape)
    {
        mBuilder.AppendLine("\tEnd of shape");
        return VisitorAction.Continue;
    }

    private readonly StringBuilder mBuilder;
}

Shows how to use a DocumentVisitor implementation to remove all hidden content from a document.

public void RemoveHiddenContentFromDocument()
{
    Document doc = new Document(MyDir + "Hidden content.docx");
    RemoveHiddenContentVisitor hiddenContentRemover = new RemoveHiddenContentVisitor();

    // Below are three types of fields which can accept a document visitor,
    // which will allow it to visit the accepting node, and then traverse its child nodes in a depth-first manner.
    // 1 -  Paragraph node:
    Paragraph para = (Paragraph)doc.GetChild(NodeType.Paragraph, 4, true);
    para.Accept(hiddenContentRemover);

    // 2 -  Table node:
    Table table = doc.FirstSection.Body.Tables[0];
    table.Accept(hiddenContentRemover);

    // 3 -  Document node:
    doc.Accept(hiddenContentRemover);

    doc.Save(ArtifactsDir + "Font.RemoveHiddenContentFromDocument.docx");
}

/// <summary>
/// Removes all visited nodes marked as "hidden content".
/// </summary>
public class RemoveHiddenContentVisitor : DocumentVisitor
{
    /// <summary>
    /// Called when a FieldStart node is encountered in the document.
    /// </summary>
    public override VisitorAction VisitFieldStart(FieldStart fieldStart)
    {
        if (fieldStart.Font.Hidden)
            fieldStart.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a FieldEnd node is encountered in the document.
    /// </summary>
    public override VisitorAction VisitFieldEnd(FieldEnd fieldEnd)
    {
        if (fieldEnd.Font.Hidden)
            fieldEnd.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a FieldSeparator node is encountered in the document.
    /// </summary>
    public override VisitorAction VisitFieldSeparator(FieldSeparator fieldSeparator)
    {
        if (fieldSeparator.Font.Hidden)
            fieldSeparator.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a Run node is encountered in the document.
    /// </summary>
    public override VisitorAction VisitRun(Run run)
    {
        if (run.Font.Hidden)
            run.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a Paragraph node is encountered in the document.
    /// </summary>
    public override VisitorAction VisitParagraphStart(Paragraph paragraph)
    {
        if (paragraph.ParagraphBreakFont.Hidden)
            paragraph.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a FormField is encountered in the document.
    /// </summary>
    public override VisitorAction VisitFormField(FormField formField)
    {
        if (formField.Font.Hidden)
            formField.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a GroupShape is encountered in the document.
    /// </summary>
    public override VisitorAction VisitGroupShapeStart(GroupShape groupShape)
    {
        if (groupShape.Font.Hidden)
            groupShape.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a Shape is encountered in the document.
    /// </summary>
    public override VisitorAction VisitShapeStart(Shape shape)
    {
        if (shape.Font.Hidden)
            shape.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a Comment is encountered in the document.
    /// </summary>
    public override VisitorAction VisitCommentStart(Comment comment)
    {
        if (comment.Font.Hidden)
            comment.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a Footnote is encountered in the document.
    /// </summary>
    public override VisitorAction VisitFootnoteStart(Footnote footnote)
    {
        if (footnote.Font.Hidden)
            footnote.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when a SpecialCharacter is encountered in the document.
    /// </summary>
    public override VisitorAction VisitSpecialChar(SpecialChar specialChar)
    {
        Console.WriteLine(specialChar.GetText());

        if (specialChar.Font.Hidden)
            specialChar.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when visiting of a Table node is ended in the document.
    /// </summary>
    public override VisitorAction VisitTableEnd(Table table)
    {
        // The content inside table cells may have the hidden content flag, but the tables themselves cannot.
        // If this table had nothing but hidden content, this visitor would have removed all of it,
        // and there would be no child nodes left.
        // Thus, we can also treat the table itself as hidden content and remove it.
        // Tables which are empty but do not have hidden content will have cells with empty paragraphs inside,
        // which this visitor will not remove.
        if (!table.HasChildNodes)
            table.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when visiting of a Cell node is ended in the document.
    /// </summary>
    public override VisitorAction VisitCellEnd(Cell cell)
    {
        if (!cell.HasChildNodes && cell.ParentNode != null)
            cell.Remove();

        return VisitorAction.Continue;
    }

    /// <summary>
    /// Called when visiting of a Row node is ended in the document.
    /// </summary>
    public override VisitorAction VisitRowEnd(Row row)
    {
        if (!row.HasChildNodes && row.ParentNode != null)
            row.Remove();

        return VisitorAction.Continue;
    }
}

See Also

DocumentVisitor.VisitShapeEnd DocumentVisitor.VisitSmartTagEnd