SemanticValue.ContainsKey(String) 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
表示目前 SemanticValue 實例集合是否包含具有特定金鑰字串的子 SemanticValue 實例。
public:
virtual bool ContainsKey(System::String ^ key);
public bool ContainsKey(string key);
abstract member ContainsKey : string -> bool
override this.ContainsKey : string -> bool
Public Function ContainsKey (key As String) As Boolean
參數
- key
- String
String包含用來識別 在當前 SemanticValue下 的SemanticValue子實例的鍵串。
傳回
若找到bool帶有該字串true標記的子實例SemanticValue,則回傳 key,false若找不到。
實作
範例
以下範例展示了一個處理事件處理程序的處理器 SpeechRecognized ,該事件旨在處理改變前景與背景顏色的指令。
處理已識別但無語意結構的片語後,處理器會使用 ContainsKey (applyChgToBackground, colorRGBValueList, 或 colorStringList)) 檢查是否有適當的鍵,然後處理語意組織的資料。
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;
};
備註
你只能在執行時依照鍵值存取資料,例如檢查 語意[“myKey”]。價值,這會產生例外。 我們建議你在使用 ContainsKey 給定實例Item[]前先查詢物件SemanticValue。