This example will provide a TextBox editor for any property of type DateTime as well as any property with the defined property names:
<extToolkit:PropertyGrid>
<extToolkit:PropertyGrid.EditorDefinitions>
<extToolkit:EditorDefinition TargetType="{x:Type sys:DateTime}">
<extToolkit:EditorDefinition.Properties>
<sys:String>FirstName</sys:String>
<sys:String>LastName</sys:String>
</extToolkit:EditorDefinition.Properties>
<extToolkit:EditorDefinition.EditorTemplate>
<DataTemplate>
<TextBox Text="{Binding Value}" />
</DataTemplate>
</extToolkit:EditorDefinition.EditorTemplate>
</extToolkit:EditorDefinition>
</extToolkit:PropertyGrid.EditorDefinitions>
</extToolkit:PropertyGrid>
You can also target just a Type or just property names.
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