筆跡分隔器範例

發行項
06/13/2023

此範例是以 Ink 集合範例為基礎。它示範如何使用 Divider 物件來分析筆跡輸入。

更新表單時，範例會在每個分析單位周圍繪製周框，並分成字組、線條、段落和繪圖。除了使用不同的色彩之外，這些矩形會以不同的數量放大，以確保其他人不會遮蔽任何矩形。下表指定每個分析單位的色彩和放大。

分析單位	色彩	圖元放大
Word	綠色	1
折線圖	桃紅色	3
Paragraph	藍色	5
繪圖	紅色	1

設定表單

當表單載入時，會建立 Divider 物件。會建立 InkOverlay物件，並與表單上的面板相關聯。然後事件處理常式會附加至 InkOverlay 物件，以追蹤何時新增和刪除筆劃。然後，如果辨識器可供使用，則會將預設辨識器的 RecognizerCoNtext 物件指派給 Divider。然後會設定 Divider 物件的 LineHeight 屬性，並將 InkOverlay 物件的 Strokes 集合指派給 Divider。最後，已啟用 InkOverlay 物件。

// Create the ink overlay and associate it with the form
myInkOverlay = new Microsoft.Ink.InkOverlay(DrawArea.Handle);

// Set the erasing mode to stroke erase.
myInkOverlay.EraserMode = InkOverlayEraserMode.StrokeErase;

// Hook event handler for the Stroke event to myInkOverlay_Stroke.
// This is necessary since the application needs to pass the strokes 
// to the ink divider.
myInkOverlay.Stroke += new InkCollectorStrokeEventHandler(myInkOverlay_Stroke); 

// Hook the event handler for StrokeDeleting event to myInkOverlay_StrokeDeleting.
// This is necessary as the application needs to remove the strokes from 
// ink divider object as well.
myInkOverlay.StrokesDeleting += new InkOverlayStrokesDeletingEventHandler(myInkOverlay_StrokeDeleting);

// Hook the event handler for StrokeDeleted event to myInkOverlay_StrokeDeleted.
// This is necessary to update the layout analysis result when automatic layout analysis
// option is selected.
myInkOverlay.StrokesDeleted += new InkOverlayStrokesDeletedEventHandler(myInkOverlay_StrokeDeleted);

// Create the ink divider object
myInkDivider = new Divider();

// Add a default recognizer context to the divider object
// without adding the recognizer context, the divider would
// not use a recognizer to do its word segmentation and would
// have less accurate results.
// Adding the recognizer context slows down the call to 
// myInkDivider.Divide though.
// It is possible that there is no recognizer installed on the
// machine for this language. In that case the divider does
// not use a recognizer to improve its accuracy.
// Get the default recognizer if any
try
{
    Recognizers recognizers = new Recognizers();
     myInkDivider.RecognizerContext = recognizers.GetDefaultRecognizer().CreateRecognizerContext();
}
catch (InvalidOperationException)
{
     //We are in the case where no default recognizers can be found
}

    // The LineHeight property helps the InkDivider distinguish between 
    // drawing and handwriting. The value should be the expected height 
    // of the user's handwriting in ink space units (0.01mm).
    // Here we set the LineHeight to 840, which is about 1/3 of an inch.
    myInkDivider.LineHeight = 840;

// Assign ink overlay's strokes collection to the ink divider
// This strokes collection is updated in the event handler
myInkDivider.Strokes = myInkOverlay.Ink.Strokes;

// Enable ink collection
myInkOverlay.Enabled = true;

Divider物件的Strokes集合必須與InkOverlay物件的Strokes集合保持同步， (透過InkOverlay 物件的 Ink屬性) 存取。為了確保發生這種情況，InkOverlay 物件的 Stroke 事件處理常式會撰寫如下。請注意，事件處理常式會先測試 EditingMode 是否設定為 Ink 以篩選掉橡皮擦筆劃。如果使用者已要求自動設定分析，則應用程式會呼叫表單的 DivideInk 方法，並重新整理繪圖區域。

private void myInkOverlay_Stroke(object sender, InkCollectorStrokeEventArgs e )
{
    // Filter out the eraser stroke.
    if(InkOverlayEditingMode.Ink == myInkOverlay.EditingMode)
    {
        // Add the new stroke to the ink divider's strokes collection
        myInkDivider.Strokes.Add(e.Stroke);
        
        if(miAutomaticLayoutAnalysis.Checked)
        {
            // Call DivideInk
            DivideInk();

            // Repaint the screen to reflect the change
            DrawArea.Refresh();
        }
    }
}

分割筆跡

當使用者按一下 [檔案] 功能表上的 [Divide] 時， Divide 方法會在 Divideer 物件上呼叫。如果有的話，會使用預設辨識器。

DivisionResult divResult = myInkDivider.Divide();

變數 divResult 所參考的結果DivisionResult物件會傳遞至公用程式函式 getUnitBBBoxes() 。公用程式函式會針對要求的任何除法類型傳回矩形陣列：區段、線條、段落或繪圖。

myWordBoundingBoxes = getUnitBBoxes(divResult, InkDivisionType.Segment, 1);
myLineBoundingBoxes = getUnitBBoxes(divResult, InkDivisionType.Line, 3);
myParagraphBoundingBoxes = getUnitBBoxes(divResult, InkDivisionType.Paragraph, 5);
myDrawingBoundingBoxes = getUnitBBoxes(divResult, InkDivisionType.Drawing, 1);

最後，會強制重新繪製表單面板，讓周框出現。

DrawArea.Refresh();

筆跡分析結果

在公用程式函式中，會根據呼叫端所要求的除法類型，使用ResultByType方法來查詢DivisionResult物件的結果。 ResultByType 方法會傳回 DivisionUnits 集合。集合中的每個 DivisionUnit 代表繪圖、手寫的單一辨識區段、手寫線條或手寫區塊，視呼叫公用程式函式時所指定的專案而定。

DivisionUnits units = divResult.ResultByType(divType);

如果至少有一個 DivisionUnit，則會建立包含每個單位一個周框的矩形陣列。 (矩形會因在擴充變數中保留的每個單位類型不同數量而擴充，以避免重迭。)

// If there is at least one unit, we construct the rectangles
if((null != units) && (0 < units.Count))
{
    // We need to convert rectangles from ink units to
    // pixel units. For that, we need Graphics object
    // to pass to InkRenderer.InkSpaceToPixel method
    using (Graphics g = DrawArea.CreateGraphics())
    {

    // InkSpace to Pixel Space conversion setup done here. 
    // Not shown for brevity.

        // Iterate through the collection of division units to obtain the bounding boxes
        foreach(DivisionUnit unit in units)
        {
            // Get the bounding box of the strokes of the division unit
            divRects[i] = unit.Strokes.GetBoundingBox();

            // Div unit rect Ink space to Pixel space conversion done here. 
            // Not shown for brevity.

            // Inflate the rectangle by inflate pixels in both directions
            divRects[i].Inflate(inflate, inflate);

            // Increment the index
            ++i;
        }

    } // Relinquish the Graphics object
}

重新繪製表單

在上方強制重繪時，下列程式碼會執行，在筆跡周圍表單上繪製每個 DivisionUnit 的周框方塊。

private void DrawArea_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
        {
            // Create the Pen used to draw bounding boxes.
            // First set of bounding boxes drawn here are 
            // the bounding boxes of paragraphs.
            // These boxes are drawn with Blue pen.
            Pen penBox = new Pen(Color.Blue, 2);

            // First, draw the bounding boxes for Paragraphs
            if(null != myParagraphBoundingBoxes)
            {
                // Draw bounding boxes for Paragraphs
                e.Graphics.DrawRectangles(penBox, myParagraphBoundingBoxes);
            }

            // Next, draw the bounding boxes for Lines
            if(null != myLineBoundingBoxes)
            {
                // Color is Magenta pen
                penBox.Color = Color.Magenta;
                // Draw the bounding boxes for Lines
                e.Graphics.DrawRectangles(penBox, myLineBoundingBoxes);
            }
            
            // Then, draw the bounding boxes for Words
            if(null != myWordBoundingBoxes)
            {
                // Color is Green
                penBox.Color = Color.Green;
                // Draw bounding boxes for Words
                e.Graphics.DrawRectangles(penBox, myWordBoundingBoxes);
            }
            
            // Finally, draw the boxes for Drawings
            if(null != myDrawingBoundingBoxes)
            {
                // Color is Red pen
                penBox.Color = Color.Red;
                // Draw bounding boxes for Drawings
                e.Graphics.DrawRectangles(penBox, myDrawingBoundingBoxes);
            }
        }

關閉表單

表單的 Dispose 方法會處置範例中使用的 InkOverlay、 Divider、 RecognizerCoNtext 物件和 Strokes 集合。

共用方式為