WPF Designer Extensibility for TextBox

I want to modify the property table in VS 2010 that is associated with silverlight textbox. I like to add a new property to 开发者_Go百科the property table of a silverlight textbox without creating a custom control. If I want to add a property called "Default value", and I want to run custom code when the user assign it from design-time property table Can I do that? I am reading about WPF designer extensibility, but all what I can find are for custom controls with custom properties. Can we do it for an existing control?

No it is certainly not possible. You have to create a custom control thats the only way.