c# - Clear/delete & refresh button wpf -

i have made delete/clear button works, after using cannot make new search...i have refresh button doesn't work @ all. want able make ned search , thought use refresh button this.

can me? if can, please explain me example.

private void button_click(object sender, routedeventargs e) {     datagridtest.itemssource = null;  }  private void refresh_click(object sender, routedeventargs e) {     datagridtest.items.refresh(); } 

there's part of code need see can able help. if working wpf, wpf awesome mvvm design pattern.

you can check start here.

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