c# - WPF Binding Label Content to Property -

i have read several articles , can't quite seem label update when property changed. propertychanged event firing, , property updating new text label not updating. help!

xaml

 <grid.resources>      <c:userinformation x:key="mytaskdata"/>  </grid.resources>  <label name="lbltasknametitle" content="{binding path=proptaskname, updatesourcetrigger=propertychanged}"/> 

window

 userinformation t = new userinformation();                   t.proptaskname = "updated task name";  this.datacontext = t.proptaskname; 

code behind

class userinformation : inotifypropertychanged  {         private string strtaskname = "task name: ";         public string proptaskname         {             { return this.strtaskname; }             set              {                  this.strtaskname = value;                 notifypropertychanged("proptaskname");  //call method set off propertychanged event.             }         }          //inotifypropertychanged stuff           public event propertychangedeventhandler propertychanged;         private void notifypropertychanged(string propertyname)         {              if (propertychanged != null)             {                 propertychanged(this, new propertychangedeventargs(propertyname));               }         } 

updated reflect comment suggestions.

xaml should be:

<label name="lbltasknametitle" content="{binding path=proptaskname, updatesourcetrigger=propertychanged}"/>  userinformation t = new userinformation();                t.proptaskname = "updated task name"; this.datacontext = t;