Attached propedrties in WPF and event wiring -

i have attached property (e.g. capitalizing text inside textbox). obvoiusly must subscribe textbox's textchanged event capitalize every time text updates.

public class capitalize {     // enabling/disabling capitalization     public static readonly dependencyproperty enabledproperty;     private static void onenabledchanged(         dependencyobject d,          dependencypropertychangedeventargs e)     {         var tb = d textbox;         if ((bool)e.newvalue)         {             tb.textchanged += new textchangedeventhandler(tb_textchanged);         }         else         {             tb.textchanged -= new textchangedeventhandler(tb_textchanged);         }     } } 

as see add event handlers textbox (if understand correctly) creates strong reference. mean because of strong ref gc cannot collect textbox? if yes - @ point should unwire event textbox can collected?

the reference goes other way around, i.e. text box holds reference event handler. there no possibility memory leaks.