WPF：將值從綁定數據傳遞給驗證規則

快速的問題。我有一個驗證器在WPF中配置，檢查以確保值在特定範圍內。這很好。見下面的代碼：WPF：將值從綁定數據傳遞給驗證規則

<TextBox Name="valueTxt" Style="{StaticResource SquareBox}" GotKeyboardFocus="amountTxt_GotKeyboardFocus" GotMouseCapture="amountTxt_GotMouseCapture" LostFocus="boxLostFocus" Height="25" Width="50"> 
          <TextBox.Text> 
           <Binding Path="UnitCost" NotifyOnValidationError="True"> 
            <Binding.ValidationRules> 
             <local:ValidDecimal MaxAmount="1000"></local:ValidDecimal> 
            </Binding.ValidationRules> 
            <Binding.Converter> 
             <local:CurrencyConverter addPound="False" /> 
            </Binding.Converter> 
           </Binding> 
          </TextBox.Text> 
         </TextBox>

但是，我想通過驗證程序另一塊數據從綁定的數據。我以爲我可以將其添加到驗證的delcaration像這樣：

<local:ValidDecimal MaxAmount="1000" SKU="{Binding Path=tblProducts.ProductSKU}"></local:ValidDecimal>

然而，似乎是我不能以這種方式訪問的SKU值。

有什麼建議嗎？

感謝，

編輯可能是值得指出的是，SKU簡直就是我的驗證聲明的字符串，像這樣：

public class ValidDecimal : ValidationRule 
{ 
    public int MaxAmount { get; set; } 
    public string SKU { get; set; } 

    public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo) 
    { 
     //validate the value as a decimal in to two decimal places 
     string cost = (string)value; 
     try 
     { 

      decimal decCost = decimal.Parse(cost); 
      if (SKU != "85555") 
      { 
       if (decCost <= 0 || decCost > MaxAmount) 
       { 
        return new ValidationResult(false, "Amount is not within valid range"); 
       } 
      } 
      return new ValidationResult(true, null); 

     } 
     catch (Exception ex) 
     { 
      return new ValidationResult(false, "Not a valid decimal value"); 
     } 
    } 
}

來源

2010-08-02 Sergio