RecognizerContext.Recognition Event
Assembly: Microsoft.Ink (in microsoft.ink.dll)
'Declaration Public Event Recognition As RecognizerContextRecognitionEventHandler 'Usage Dim instance As RecognizerContext Dim handler As RecognizerContextRecognitionEventHandler AddHandler instance.Recognition, handler
/** @event */ public void add_Recognition (RecognizerContextRecognitionEventHandler value) /** @event */ public void remove_Recognition (RecognizerContextRecognitionEventHandler value)
In JScript, you can handle the events defined by a class, but you cannot define your own.
Not applicable.
The event handler receives an argument of type RecognizerContextRecognitionEventArgs that contains data about this event.
When you create a RecognizerContextRecognitionEventHandler delegate, you identify the method that handles the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate.
The behavior of the application programming interface (API) is unpredictable if you try to gain access to the original RecognizerContext object from the recognition event handler. Do not attempt to do this. Instead, if you need to do this, create a flag and set it in the Recognition event handler. Then you can poll that flag to determine when to change the RecognizerContext properties outside of the event handler.
This C# example tracks each stroke made in an InkCollector object, theInkCollector, and calls the BackgroundRecognize method, which subsequently causes a Recognition event to occur. The results of the recognition appear in the text box, theTextBox.
using System; using System.Drawing; using System.Windows.Forms; using Microsoft.Ink; class RecognitionEventForm : System.Windows.Forms.Form { private TextBox theTextBox; InkCollector theInkCollector; Strokes theStrokes; RecognizerContext theRecognizerContext; public RecognitionEventForm() { // Initialize the form and the textbox. // Call SuspendLayout while we adjust things. this.theTextBox = new System.Windows.Forms.TextBox(); this.SuspendLayout(); this.theTextBox.Dock = System.Windows.Forms.DockStyle.Bottom; this.theTextBox.Location = new System.Drawing.Point(0, 300); this.theTextBox.Size = new System.Drawing.Size(350, 20); this.theTextBox.Text = ""; this.ClientSize = new System.Drawing.Size(350, 320); this.Controls.AddRange(new System.Windows.Forms.Control[] {this.theTextBox}); this.Text = "Recognition Event Demo"; this.ResumeLayout(false); // Create new ink collector and recognizer context theInkCollector = new InkCollector(Handle); theRecognizerContext = new RecognizerContext(); // Initialize the recognizer's strokes // and assign them to the recognizer context. theStrokes = theInkCollector.Ink.Strokes; theRecognizerContext.Strokes = theStrokes; // Install event handlers. theInkCollector.Stroke += new InkCollectorStrokeEventHandler(Stroke_Event); theRecognizerContext.Recognition += new RecognizerContextRecognitionEventHandler(Recognition_Event); // Enable the ink collector theInkCollector.Enabled = true; } public static void Main() { Application.Run(new RecognitionEventForm()); } // Stroke event handler private void Stroke_Event(object sender, InkCollectorStrokeEventArgs e) { // When a new stroke is collected, // add it to the recognizer's strokes collection. theStrokes.Add(e.Stroke); // Tell the context to recognize its strokes. theRecognizerContext.BackgroundRecognize(); } // Recognition Event Handler private void Recognition_Event(object sender, RecognizerContextRecognitionEventArgs e) { // Update the Text box with the top string of the result theTextBox.Text = e.Text; } // Event handler for the form's closed event private void RecognitionEventForm_Closed(object sender, System.EventArgs e) { theInkCollector.Dispose(); theInkCollector = null; theRecognizerContext.Dispose(); theRecognizerContext = null; } }
This Microsoft® Visual Basic® .NET example tracks each stroke made in an InkCollector object, theInkCollector, and calls the BackgroundRecognize method, which subsequently causes a Recognition event to occur. The results of the recognition appear in the text box, theTextBox.
Imports Microsoft.Ink Public Class Form1 Inherits System.Windows.Forms.Form '... Code to create Form1 and theTextBox goes here. Dim theInkCollector As InkCollector Dim theStrokes As Strokes Dim theRecognizerContext As RecognizerContext Dim theRecognitionResult As RecognitionResult Private Sub Stroke_Event(ByVal sender As Object, _ ByVal e As InkCollectorStrokeEventArgs) 'When a new stroke is collected, add it to 'the RecognizerContext's strokes collection theStrokes.Add(e.Stroke) 'Tell the RecognizerContext to recognize theRecognizerContext.BackgroundRecognize() End Sub Private Sub Recognize_Event( _ ByVal sender As Object, _ ByVal e As RecognizerContextRecognitionEventArgs) 'Update the Text box with the top result theTextBox.Text = e.Text End Sub Private Sub Form1_Load(ByVal sender As Object, _ ByVal e As System.EventArgs) Handles MyBase.Load theInkCollector = New InkCollector(Handle) 'Create new RecognizerContext theRecognizerContext = New RecognizerContext() 'Initialize the recognizer's strokes 'and assign them to the RecognizerContext theStrokes = theInkCollector.Ink.Strokes theRecognizerContext.Strokes = theStrokes 'Add the handler for the Stroke event AddHandler theInkCollector.Stroke, AddressOf Stroke_Event 'Handle Recognition event AddHandler theRecognizerContext.Recognition, _ AddressOf Recognize_Event 'Enable the ink collector theInkCollector.Enabled = True End Sub ' Event handler for the form's closed event Private Sub Form1_Closed(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Closed theInkCollector.Dispose() Set theInkCollector = Nothing theRecognizerContext.Dispose() Set theRecognizerContext = Nothing End Sub End Class
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.