c# - Filter Listview WPF -

i have "attached property" , need generic. in example, work properly, need cast variable of type "employee". possible create more generic, "attached property" more generic, rather casting "employee", converted string , use listview

public static readonly dependencyproperty filtersourceproperty =       dependencyproperty.registerattached("filtersource", typeof (textbox), typeof (listviewextension),             new frameworkpropertymetadata(null, ontextboxset));  public static textbox getfiltersource(dependencyobject dobj) {     return (textbox)dobj.getvalue(filtersourceproperty); }  public static void setfiltersource(dependencyobject dobj, textbox value) {     dobj.setvalue(filtersourceproperty, value); }  private static void ontextboxset(dependencyobject dobj, dependencypropertychangedeventargs e) {     var listview = dobj listview;     var textbox = e.newvalue textbox;      if ((listview != null) && (textbox != null))     {         textbox.textchanged += delegate(object sender, textchangedeventargs tcea)         {             var view = collectionviewsource.getdefaultview(listview.itemssource);             if (view == null) return;             view.filter += item =>             {                 var textfilter = ((textbox)sender).text;                 var itempl = (employee)item;                 return itempl.username.contains(textfilter);             };         };     } } 

in .xaml

<listview ...> ... ... tools:listviewextension.filtersource="{binding elementname=txtfilter}" ... ... </listview 

>

does not require use of textbox in ontextboxset.

try :

 public static readonly dependencyproperty filtersourceproperty =   dependencyproperty.registerattached("filtersource", typeof(string), typeof(extentions),         new frameworkpropertymetadata(null, ontextboxset));      public static string getfiltersource(dependencyobject dobj)     {         return (string)dobj.getvalue(filtersourceproperty);     }      public static void setfiltersource(dependencyobject dobj, string value)     {         dobj.setvalue(filtersourceproperty, value);     }      private static void ontextboxset(dependencyobject dobj, dependencypropertychangedeventargs e)     {         var listview = dobj listview;         var text = e.newvalue string;          if ((listview == null) || (text == null)) return;          var view = collectionviewsource.getdefaultview(listview.itemssource);         if (view == null) return;         view.filter += item =>         {             var itempl = (employee) item;             return itempl.username.contains(text);         };     } 

in xaml :(set path of element)

<listview tools:listviewextension.filtersource="{binding elementname=txtfilter,path=text,mode=twoway,updatesourcetrigger=propertychanged}"/> 

edited :

private static void ontextboxset(dependencyobject dobj, dependencypropertychangedeventargs e)     {         var listview = dobj listview;         var text = e.newvalue string;          if ((listview == null) || (text == null)) return;          var view = collectionviewsource.getdefaultview(listview.itemssource);         if (view == null) return;         view.filter += item =>         {             var type = item.gettype();             if (type == typeof(employee))             {                 var itempl = (employee)item;                 return itempl.username.contains(text);             }             if (type == typeof(person))             {                 var itempl = (person)item;                 return itempl.name.contains(text);             }             //and more types ..............              return false;         };     }