今天做數(shù)據(jù)驗證控件時遇到了個問題，自定義集合控件中的集合項的屬性無法進(jìn)行數(shù)據(jù)綁定，先列一下關(guān)鍵部分的代碼：

　　驗證控件類定義：

public class Validator : Control
{
public static readonly DependencyProperty ItemsProperty
= DependencyProperty.Register(
"Items",
typeof(ValidatorItemCollection),
typeof(Validator),
new PropertyMetadata(null));

public ValidatorItemCollection Items
{
get { return (ValidatorItemCollection)base.GetValue(ItemsProperty); }
set { base.SetValue(ItemsProperty, value); }
}
……此處略去很多字
}

　　驗證規(guī)則集合類定義：

public class ValidatorItemCollection : ObservableCollection<ValidatorItem>
{
}

　　驗證規(guī)則類定義：

public class ValidatorItem : FrameworkElement
{
public bool IsRequired { get; set; }

public static readonly DependencyProperty ValidateSenderProperty
= DependencyProperty.Register(
"ValidateSender",
typeof(string),
typeof(ValidatorItem),
new PropertyMetadata(string.Empty));

public string ValidateSender
{
get { return (string)GetValue(ValidatorItem.ValidateSenderProperty); }
set
{
SetValue(ValidateSenderProperty, value);
}
}
}

　　XAML代碼：

<local:Validator x:Name="validator" AutoValidate="{Binding Path=IsEnabled}">
<local:Validator.Items>
<local:ValidatorItem x:Name="item1" IsRequired="True"
ValidateSender="{Binding Path=Name, ElementName=textBox1}">
</local:ValidatorItem>
</local:Validator.Items>
</local:Validator>

　　有關(guān)Binding、ObservableCollection的資料，繼承的基類也換來換去，還通過反編譯的手段找了DomainDataSource類的相關(guān)定義來對照，依然不能解決問題。后來

　　直接在C#代碼里綁定，無意中發(fā)現(xiàn)item1居然為null，料想原來是visual tree出了問題：定義的ValidatorItem根本沒有加載到控件樹中，雖然使用Validator.Items

　　是可以成功訪問到的。

　　于是乎，到處找關(guān)于FindName方法的資料，了解到WPF中需要通過RegisterName來注冊NameScope，可是silverlight里根本沒有類似方法。

　　最終，在這個帖子里找到了解決辦法：//stackoverflow.com/questions/4571577/silverlight-usercontrol-child-controls-and-findname

　　這是給出的回答：

　　It may be difficult to do at this point but the best course of action would probably be to derive your control from ItemsControl instead of UserControl. Then you wouldn't have the problem with name scopes.

　　I suppose as a workaround you could do a dive into the control with VisualTreeHelper to manually set the tbTest field

　　后來將Validator類改為繼承自ItemsControl，再把Items屬性、ItemsProperty干掉，終于Binding成功了。不過這種方法似乎也不是太好，如果我的Validator類中需要定義好幾個集合屬性咋辦?