private void textChangedHandler(Object sender, TextChangedEventArgs e) { String fromName = (((TextBox)sender).Name).ToString().ToUpper(); float fromValue; if (float.TryParse(((TextBox)sender).Text, out fromValue)) { foreach (KeyValuePair <String, float> currency in currencies) { String toName = currency.Key.ToString().ToUpper(); if (!fromName.Equals(toName)) { TextBlock temp = (TextBlock)RootView.FindName("textBlockFrom" + fromName + "For" + toName); temp.Text = currency.Key + " = " + (fromValue * ((float)currency.Value / (float)currencies[fromName])).ToString(); } } } else { foreach (KeyValuePair <String, float> currency in currencies) { String toName = currency.Key.ToString().ToUpper(); if (!fromName.Equals(toName)) { TextBlock temp = (TextBlock)RootView.FindName("textBlockFrom" + fromName + "For" + toName); temp.Text = currency.Key + " = Invalid"; } } } }