数据绑定自定义WPF控件不'；行不通

我为DateTimePicker编写了一个自定义控件，但是绑定值没有正确地传递给属性

<cc:DateTimePicker SelDate="{Binding RA_EFFECTIVE_DATE}"/> <!-- Doesn't work -->
<cc:DateTimePicker SelDate="1.1.2014"/> <!-- Works? Which means I can see the value inside setter SelDate correctly -->

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提前感谢…

检查Visual studio的输出窗口中是否存在与

RA\u EFFECTIVE\u DATE

相关的绑定错误。您是否为RA\u EFFECTIVE\u DATE属性实现了绑定？我似乎有绑定问题。。。

    public static readonly DependencyProperty SelDateProperty =
       DependencyProperty.Register(
       "SelDate",
       typeof(DateTime?),
       typeof(DateTimePicker),
       new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnSelectedDateChanged, CoerceSelectedDate));



    public DateTime? SelDate
    {
        get { return (DateTime?)GetValue(SelDateProperty); }
        set { SetValue(SelDateProperty, value); }
    }