xaml - How exactly do Attached Properties work in WPF? -

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How do I'm a bit misleading how attached properties actually transmits its values ​​to the parent or child elements I TextElement.FontFamily that the property was assigned to value (a seemingly perfect reason to get the elements of the child's parent) to the downstream operations, baby grid. Column creates an original item to display that child in a special item (a seemingly upstream operation, for the child's parents). How to find attached property values ​​either to flow or down? It's wrong in your conception that there is a piece missing that will put all this in perspective, or 

   & Lt; Column width = "*" /> & Lt; /Grid.ColumnDefinitions> & Lt; Button grid Column = "1" content = "my button" /> & Lt; / Grid & gt; & Lt; / StackPanel & gt;

There are two concepts: Dependency Properties and Enclosed Dependency Properties , "Attached Properties" are dependency properties, and such support dependencies.

About the basic dependency properties, a very rough will be a statement that they basically WPF parent of elements inherit their values ​​(logical / visual) tree. Inherit is set with the flag, and in many cases it is one such.

Attribute attributes are properties that can be set on any wpf object (basically, at least a dependency object) through the method. The purpose for this mechanism is "attachment" to the information of other objects required by the original objects, rather to place the items within themselves, for example an object, for an attached grid, the necessary assets to render their area.

Dependency attributes are obtained from the WPF object system "Downward" automatically.

Enclosed properties are explicitly examined in the code of the "top side" in the case of the grid, where it is a matter of determining the place of its place, this is the grid.Row And checks for the value of the Grid.Column Attached Properties.

It is also often custom made to make custom attributes that are attached to objects in some way (for example).

As an additional note, Inheriting does not set a good example is found in Grid.Row and Grid.Column inherited traits flag attached property

TextElement.FontFamily, the reflector :. 

  FontFamilyProperty = DependencyProperty.RegisterAttached ( "FontFamily", Taipf (Fontfamili), Taipf (Text Element), New Fremvrkproprtimatetata (Sistmfont. Mesejfontili, Fremvrkproprtimatdetaopeshnskformvrkproprtimatetaopeshnsoffiferrender | Fremvrkproprtimatdataopeshnsfifersmejr), New Vaddetacolbak (Tekstelement. ISWelliFontFamily));   
 Grid From the ROR, Reflector:  
  Ropotpot = Dependency Property. Registrar Attached ( "row", Taipf (Int), Taipf (grid), New Fremvrkproprtimatdata (0, New PropertyChangedCallback (GridkOnCellAttachedPropertyChanged)), new ValidateValueCallback (Grid.IsIntValueNotNegative));

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