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c#wpfdatacontext

Check if DataContext is Inherited via code

I want to check if a DataContext value for a UserControl is inherited from parent element or if was directly set on the current UserControl (local value), via C# code.

I can find this information by using visual studio wpf visualizer tool, but I can't figure out how to do this via code.

I have attached a screenshot with the information that I want (yellow highlighted). enter image description here

Solution

  • Use DependencyPropertyHelper:

    var helper = DependencyPropertyHelper.GetValueSource(
    control,
    FrameworkElement.DataContextProperty);

Debug.WriteLine(helper.BaseValueSource);

    The type of BaseValueSource is the following enum (from .NET Reference Source):

    public enum BaseValueSource
{
    /// <summary> The source is not known by the Framework. </summary>
    Unknown                 = BaseValueSourceInternal.Unknown,
    /// <summary> Default value, as defined by property metadata. </summary>
    Default                 = BaseValueSourceInternal.Default,
    /// <summary> Inherited from an ancestor. </summary>
    Inherited               = BaseValueSourceInternal.Inherited,
    /// <summary> Default Style for the current theme. </summary>
    DefaultStyle            = BaseValueSourceInternal.ThemeStyle,
    /// <summary> Trigger in the default Style for the current theme. </summary>
    DefaultStyleTrigger     = BaseValueSourceInternal.ThemeStyleTrigger,
    /// <summary> Style setter. </summary>
    Style                   = BaseValueSourceInternal.Style,
    /// <summary> Trigger in the Template. </summary>
    TemplateTrigger         = BaseValueSourceInternal.TemplateTrigger,
    /// <summary> Trigger in the Style. </summary>
    StyleTrigger            = BaseValueSourceInternal.StyleTrigger,
    /// <summary> Implicit Style reference. </summary>
    ImplicitStyleReference  = BaseValueSourceInternal.ImplicitReference,
    /// <summary> Template that created the element. </summary>
    ParentTemplate          = BaseValueSourceInternal.ParentTemplate,
    /// <summary> Trigger in the Template that created the element. </summary>
    ParentTemplateTrigger   = BaseValueSourceInternal.ParentTemplateTrigger,
    /// <summary> Local value. </summary>
    Local                   = BaseValueSourceInternal.Local,
}