SemanticValue.Count Property

 

Returns the number of child SemanticValue objects under the current SemanticValue instance.

Namespace:   System.Speech.Recognition
Assembly:  System.Speech (in System.Speech.dll)

public int Count { get; }

Property Value

Type: System.Int32

The number of child SemanticValue objects under the current SemanticValue.

Recognition results that do not make use of semantic parsing always have a Count value of zero, as well as a Value of null.

The following example shows a handler for a SpeechRecognized event designed to handle commands to change foreground and background color.

The handler identifies recognized phrases that have no underlying semantic structure by detecting a Count of zero and a Value of null. This recognition output is then processed directly by parsing the raw text.

In other cases, the handler uses keys to obtain the RGB components of a color name, to determine whether the command will change the foreground or background, or to indicate that no valid key was found.


newGrammar.SpeechRecognized +=
  delegate(object sender, SpeechRecognizedEventArgs eventArgs) 
  {

    // Retrieve the value of the semantic property.
    bool changeBackGround = true;
    string errorString = "";
    SemanticValue semantics = eventArgs.Result.Semantics;

    Color newColor = Color.Empty;

    try 
    {
      if (semantics.Count == 0 && semantics.Value==null)
      {
        // Signifies recognition by a grammar with no semantics.
        // Parse the string, assuming that the last word is color,
        //  searching for background or foreground in input.
        if (eventArgs.Result.Text.Contains("foreground")) 
        {
          changeBackGround = false;
        }
        string cName = eventArgs.Result.Words[eventArgs.Result.Words.Count - 1].Text;
        newColor = Color.FromName(cName);

      }
      else if (semantics.ContainsKey("colorStringList") ^ semantics.ContainsKey("colorRGBValueList")) 
      {

        // Determine whether to change background or foreground.
        if (semantics.ContainsKey("applyChgToBackground")) 
        {
          changeBackGround = semantics["applyChgToBackground"].Value is bool;
        }

        // Get the RGB color value.
        if (semantics.ContainsKey("colorStringList")) 
        {
          newColor = Color.FromName((string)semantics["colorStringList"].Value);
        }
        if (semantics.ContainsKey("colorRGBValueList")) 
        {
          newColor = System.Drawing.Color.FromArgb((int)semantics["colorRGBValueList"].Value);
        }
      }
      else 
      {

        // Throw an exception if the semantics do not contain the keys we
        // support.
        throw(new Exception("Unsupported semantics keys found."));
      }
    }

    catch (Exception exp) 
    {
      MessageBox.Show(String.Format("Unable to process color semantics.:\n{0}\n", exp.Message));
      return;
    }

    // Change colors, either foreground or background.
    if (changeBackGround) 
    {
      BackColor = newColor;
      float Bright = BackColor.GetBrightness();
      float Hue = BackColor.GetHue();
      float Sat = BackColor.GetSaturation();
      // Make sure that text is readable regardless of background.
      if (BackColor.GetBrightness() <= .50) 
      {
        ForeColor = Color.White;
      }
      else 
      {
        ForeColor = Color.Black;
      }
    }
    else 
    {
      ForeColor = newColor;
      float Bright = ForeColor.GetBrightness();
      float Hue = ForeColor.GetHue();
      float Sat = ForeColor.GetSaturation();

      // Make sure that text is readable regardless of Foreground.
      if (ForeColor.GetBrightness() <= .50) 
      {
        BackColor = Color.White;
      }
      else 
      {
        BackColor = Color.Black;
      }
    }
    return;
  };

.NET Framework
Available since 3.0
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