ContextNode 类

表示在墨迹分析过程中创建的对象树中的一个节点。

命名空间：  System.Windows.Ink
程序集：  IAWinFX（在 IAWinFX.dll 中）

语法

声明
Public Class ContextNode
用法
Dim instance As ContextNode

public class ContextNode

public ref class ContextNode

public class ContextNode

public class ContextNode

备注

在 InkAnalyzer 执行墨迹分析后，它以 ContextNode 对象树的形式表示结果。RootNode 位于树的顶部；在树下方的位置越深，所表示的笔画集合就越小。这些节点可以是单词组（例如段落或行）、分析的墨迹（例如单词或绘图）或各种其他类型。（有关完整列表，请参见 ContextNodeType 类。）

可以手动向 InkAnalyzer 添加节点（如 AnalysisHintNode、ImageNode 和 TextWordNode 对象等）。

对于错误的输入，此方法引发 ArgumentException 异常。

示例

此示例获取名为 theInkAnalyzer 的 InkAnalyzer，并使用其 ContextNode 树来填充名为 theTreeView 的 [System.Windows.Controls.TreeView]。当选中树视图中的某个节点时，该节点的关联笔画将设置为以红色显示。[System.Windows.FrameworkElement.Tag] 属性用于在树节点与树节点所表示的上下文节点之间进行映射。

Private Sub BuildTree() 
    ' Remove the old nodes from the TreeView and add the current results.
    Me.theResultsTreeView.Items.Clear()

    Dim rootNode As New TreeViewItem()
    rootNode.Tag = Me.theInkAnalyzer.RootNode
    rootNode.Header = theInkAnalyzer.RootNode.ToString()

    Me.theResultsTreeView.Items.Add(rootNode)

    WalkTree(Me.theInkAnalyzer.RootNode, rootNode)

End Sub 'BuildTree


Private Shared Sub WalkTree(ByVal parentContextNode As ContextNode, ByVal parentTreeNode As TreeViewItem) 

    parentTreeNode.IsExpanded = True

    For Each theContextSubnode As ContextNode In parentContextNode.SubNodes
        Dim newTreeNode As New TreeViewItem()
        newTreeNode.Header = theContextSubnode.ToString()

        If TypeOf theContextSubnode Is InkWordNode Then
            newTreeNode.Header += ": " + CType(theContextSubnode, InkWordNode).GetRecognizedString()
        ElseIf TypeOf theContextSubnode Is InkDrawingNode Then
            newTreeNode.Header += ": " + CType(theContextSubnode, InkDrawingNode).GetShapeName()
        End If

        ' If the context node is confirmed, add a note to the
        ' tree view item.
        If (theContextSubnode.IsConfirmed(ConfirmationType.NodeTypeAndProperties)) Then

            newTreeNode.Header += " Confirmed."
        End If


        ' Add the context node as a tag of the tree view item and
        ' add the new tree view item to the parent node.
        newTreeNode.Tag = theContextSubnode
        parentTreeNode.Items.Add(newTreeNode)

        WalkTree(theContextSubnode, newTreeNode)
    Next theContextSubnode

End Sub 'WalkTree

Sub theResultsTreeView_SelectedItemChanged(ByVal sender As Object, _
                                           ByVal e As RoutedPropertyChangedEventArgs(Of Object))
    Dim selectedTreeViewItem As TreeViewItem = e.NewValue '

    If selectedTreeViewItem Is Nothing Then
        Return
    End If

    ' Get the context node
    Dim selectedNode As ContextNode = CType(selectedTreeViewItem.Tag, ContextNode)

    MarkNodeAsRed(selectedNode)

    timeStampLabel.Content = ""

    ' Show selected results
    If Not (selectedNode Is Nothing) Then
        If selectedNode.Type = ContextNodeType.WritingRegion Then
            Dim writingRegion As WritingRegionNode = CType(selectedNode, WritingRegionNode)
            selectedResultsTextBox.Text = writingRegion.GetRecognizedString()
        ElseIf selectedNode.Type = ContextNodeType.Paragraph Then
            Dim paragraph As ParagraphNode = CType(selectedNode, ParagraphNode)
            selectedResultsTextBox.Text = paragraph.GetRecognizedString()
        ElseIf selectedNode.Type = ContextNodeType.Line Then
            Dim line As LineNode = CType(selectedNode, LineNode)
            selectedResultsTextBox.Text = line.GetRecognizedString()
        ElseIf selectedNode.Type = ContextNodeType.InkWord Then
            Dim inkWord As InkWordNode = CType(selectedNode, InkWordNode)
            Dim parentNode As ContextNode = inkWord.ParentNode
            If TypeOf parentNode Is LineNode Then
                Dim parentLine As LineNode = CType(parentNode, LineNode)
                ' Put parent line's recognized string into the text box
                selectedResultsTextBox.Text = parentLine.GetRecognizedString()

                ' Select the text that corresponds to the ink word
                Dim subNodes As New ContextNodeCollection(theInkAnalyzer)
                subNodes.Add(inkWord)
                Dim start As Integer
                Dim length As Integer
                parentLine.GetTextRangeFromNodes(subNodes, start, length)
                If start >= 0 AndAlso length > 0 Then
                    selectedResultsTextBox.Select(start, length)
                End If
            End If
        ElseIf selectedNode.Type = ContextNodeType.InkDrawing Then
            Dim drawingNode As InkDrawingNode = CType(selectedNode, InkDrawingNode)
            selectedResultsTextBox.Text = drawingNode.GetShapeName()
        ElseIf selectedNode.Type = ContextNodeType.InkBullet Then
            Dim bulletNode As InkBulletNode = CType(selectedNode, InkBulletNode)
            selectedResultsTextBox.Text = bulletNode.GetRecognizedString()
        ElseIf selectedNode.Type = ContextNodeType.CustomRecognizer Then
            Dim customRecognizer As CustomRecognizerNode = CType(selectedNode, CustomRecognizerNode)
            selectedResultsTextBox.Text = customRecognizer.GetRecognizedString()
        ElseIf selectedNode.Type = ContextNodeType.Object Then
            Dim selectedObject As ObjectNode = CType(selectedNode, ObjectNode)
            selectedResultsTextBox.Text = selectedObject.GetRecognizedString()
        Else
            selectedResultsTextBox.Text = ""
        End If
        If TypeOf selectedNode Is InkWordNode Then
            Dim inkWord As InkWordNode = CType(selectedNode, InkWordNode)

            ' Show the time stamp
            If inkWord.ContainsPropertyData(Me.timeStampGuid) Then
                Dim timeStamp As DateTime = CType(inkWord.GetPropertyData(Me.timeStampGuid), DateTime)
                timeStampLabel.Content = timeStamp.ToShortTimeString()
            End If
            ' Snippet to demonstrate GetPropertyDataIds
            Dim propertyDataIds As Guid() = inkWord.GetPropertyDataIds()
            ' Snippets to demonstrate loading and saving
            Dim data As Byte() = inkWord.SavePropertiesData()
            If Not inkWord.LoadPropertiesData(data) Then
                MessageBox.Show("Cannot load property data")
            End If
        End If
    End If
    PopulateLinksList(selectedNode)
    Me.currentNode = selectedNode
End Sub

Private Sub PopulateLinksList(ByVal selectedNode As ContextNode)

    linksListBox.Items.Clear()

    If selectedNode Is Nothing Then
        Return
    End If

    Dim link As ContextLink
    For Each link In selectedNode.Links
        linksListBox.Items.Add(link.SourceNode.ToString() + ", " & _
                                    link.DestinationNode.ToString() & ": " & _
                                    link.LinkDirection.ToString())
    Next
End Sub

Sub MarkNodeAsRed(ByVal selectedNode As ContextNode)
    ' Set all node strokes to black, but this one to red
    Dim stroke As Stroke
    For Each stroke In Me.theInkCanvas.Strokes
        If Not (selectedNode Is Nothing) AndAlso selectedNode.Strokes.Contains(stroke) Then
            stroke.DrawingAttributes.Color = Colors.Red
        Else
            stroke.DrawingAttributes.Color = Me.theInkCanvas.DefaultDrawingAttributes.Color
        End If
    Next stroke

End Sub 'theResultsTreeView_SelectedItemChanged 

private void BuildTree()
{
    // Remove the old nodes from the TreeView and add the current results.
    this.theResultsTreeView.Items.Clear();

    TreeViewItem rootNode = new TreeViewItem();
    rootNode.Tag = this.theInkAnalyzer.RootNode;
    rootNode.Header = theInkAnalyzer.RootNode.ToString();

    this.theResultsTreeView.Items.Add(rootNode);

    WalkTree(this.theInkAnalyzer.RootNode, rootNode);

}

private static void WalkTree(ContextNode parentContextNode, TreeViewItem parentTreeNode)
{
    // Expand the current TreeViewItem.
    parentTreeNode.IsExpanded = true;

    foreach (ContextNode theContextSubnode
        in parentContextNode.SubNodes)
    {
        TreeViewItem newTreeNode = new TreeViewItem();
        newTreeNode.Header = theContextSubnode.ToString();

        if (theContextSubnode is InkWordNode)
        {
            newTreeNode.Header += ": " +
                ((InkWordNode)theContextSubnode).GetRecognizedString();
        }
        else if (theContextSubnode is InkDrawingNode)
        {
            newTreeNode.Header += ": " +
                ((InkDrawingNode)theContextSubnode).GetShapeName();
        }

        // If the context node is confirmed, add a note to the
        // tree view item.
        if (theContextSubnode.IsConfirmed(ConfirmationType.NodeTypeAndProperties))
        {
            newTreeNode.Header += " Confirmed.";
        }

        // Add the context node as a tag of the tree view item and
        // add the new tree view item to the parent node.
        newTreeNode.Tag = theContextSubnode;
        parentTreeNode.Items.Add(newTreeNode);

        WalkTree(theContextSubnode, newTreeNode);
    }
}


void theResultsTreeView_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
{
    TreeViewItem selectedTreeViewItem = e.NewValue as TreeViewItem;

    if (selectedTreeViewItem == null)
    {
        return;
    }

    // Get the context node
    ContextNode selectedNode = (ContextNode)selectedTreeViewItem.Tag;

    MarkNodeAsRed(selectedNode);

    timeStampLabel.Content = "";

    // Show selected results
    if (selectedNode != null)
    {
        if (selectedNode.Type == ContextNodeType.WritingRegion)
        {
            WritingRegionNode writingRegion = (WritingRegionNode)selectedNode;
            selectedResultsTextBox.Text = writingRegion.GetRecognizedString();
        }
        else if (selectedNode.Type == ContextNodeType.Paragraph)
        {
            ParagraphNode paragraph = (ParagraphNode)selectedNode;
            selectedResultsTextBox.Text = paragraph.GetRecognizedString();
        }
        else if (selectedNode.Type == ContextNodeType.Line)
        {
            LineNode line = (LineNode)selectedNode;
            selectedResultsTextBox.Text = line.GetRecognizedString();
        }
        else if (selectedNode.Type == ContextNodeType.InkWord)
        {
            InkWordNode inkWord = (InkWordNode)selectedNode;
            ContextNode parentNode = inkWord.ParentNode;
            if (parentNode is LineNode)
            {
                LineNode parentLine = (LineNode)parentNode;
                // Put parent line's recognized string into the text box
                selectedResultsTextBox.Text = parentLine.GetRecognizedString();

                // Select the text that corresponds to the ink word
                ContextNodeCollection subNodes = new ContextNodeCollection(theInkAnalyzer);
                subNodes.Add(inkWord);
                int start;
                int length;
                parentLine.GetTextRangeFromNodes(subNodes, out start, out length);
                if (start >= 0 && length > 0)
                {
                    selectedResultsTextBox.Select(start, length);
                }
            }
        }
        else if (selectedNode.Type == ContextNodeType.InkDrawing)
        {
            InkDrawingNode drawingNode = (InkDrawingNode)selectedNode;
            selectedResultsTextBox.Text = drawingNode.GetShapeName();
        }
        else if (selectedNode.Type == ContextNodeType.InkBullet)
        {
            InkBulletNode bulletNode = (InkBulletNode)selectedNode;
            selectedResultsTextBox.Text = bulletNode.GetRecognizedString();
        }
        else if (selectedNode.Type == ContextNodeType.CustomRecognizer)
        {
            CustomRecognizerNode customRecognizer = (CustomRecognizerNode)selectedNode;
            selectedResultsTextBox.Text = customRecognizer.GetRecognizedString();
        }
        else if (selectedNode.Type == ContextNodeType.Object)
        {
            ObjectNode selectedObject = (ObjectNode)selectedNode;
            selectedResultsTextBox.Text = selectedObject.GetRecognizedString();
        }
        else
        {
            selectedResultsTextBox.Text = "";
        }

        if (selectedNode is InkWordNode)
        {
            InkWordNode inkWord = (InkWordNode)selectedNode;

            // Show the time stamp
            if (inkWord.ContainsPropertyData(this.timeStampGuid))
            {
                DateTime timeStamp =
                    (DateTime)inkWord.GetPropertyData(this.timeStampGuid);
                timeStampLabel.Content = timeStamp.ToShortTimeString();
            }

            // Snippet to demonstrate GetPropertyDataIds
            Guid[] propertyDataIds = inkWord.GetPropertyDataIds();
            // Snippets to demonstrate loading and saving
            byte[] data = inkWord.SavePropertiesData();
            if (!inkWord.LoadPropertiesData(data))
                MessageBox.Show("Cannot load property data");
        }

    }
    PopulateLinksList(selectedNode);
    this.currentNode = selectedNode;
}

private void PopulateLinksList(ContextNode selectedNode)
{
    linksListBox.Items.Clear();
    if (selectedNode == null)
    {
        return;
    }

    foreach (ContextLink link in selectedNode.Links)
    {
        linksListBox.Items.Add(link.SourceNode.ToString() + ", " +
                                    link.DestinationNode.ToString() + ": " +
                                    link.LinkDirection.ToString());
    }
}

private void MarkNodeAsRed(ContextNode selectedNode)
{
    // Set all node strokes to black, but this one to red
    foreach (Stroke stroke in this.theInkCanvas.Strokes)
    {
        if (selectedNode != null &&
            selectedNode.Strokes.Contains(stroke))
            stroke.DrawingAttributes.Color = Colors.Red;
        else
            stroke.DrawingAttributes.Color = 
                this.theInkCanvas.DefaultDrawingAttributes.Color;
    }
}

继承层次结构

System.Object
  System.Windows.Ink.ContextNode
    System.Windows.Ink.AnalysisHintNode
    System.Windows.Ink.CustomRecognizerNode
    System.Windows.Ink.ImageNode
    System.Windows.Ink.InkBulletNode
    System.Windows.Ink.InkDrawingNode
    System.Windows.Ink.InkWordNode
    System.Windows.Ink.LineNode
    System.Windows.Ink.ObjectNode
    System.Windows.Ink.ParagraphNode
    System.Windows.Ink.RootNode
    System.Windows.Ink.TextWordNode
    System.Windows.Ink.UnclassifiedInkNode
    System.Windows.Ink.WritingRegionNode

线程安全

此类型的任何公共 static（在 Visual Basic 中为 Shared） 成员都是线程安全的。但不保证所有实例成员都是线程安全的。

平台

Windows Vista

.NET Framework 和 .NET Compact Framework 并不是对每个平台的所有版本都提供支持。有关支持的版本的列表，请参见.NET Framework 系统要求。

版本信息

.NET Framework

受以下版本支持：3.0

另请参见

参考

ContextNode 成员

System.Windows.Ink 命名空间

InkAnalyzer.Analyze

InkAnalyzer.RootNode

System.Windows.Ink.ContextNodeType