Fixed an issue where the clipboard content isn't preserved after shutting down the app.

src/dev/impl/DevToys/App.xaml.cs

@@ -187,6 +187,18 @@ private void OnSuspending(object sender, SuspendingEventArgs e)
         {
             var deferral = e.SuspendingOperation.GetDeferral();
             //TODO: Save application state and stop any background activity
+
+            try
+            {
+                // Bug #22: Here we flush the Clipboard to make sure content in clipboard to remain available
+                // after the application shuts down.
+                Windows.ApplicationModel.DataTransfer.Clipboard.Flush();
+            }
+            catch (Exception)
+            {
+                // ignore
+            }
+
             deferral.Complete();
         }
 

src/dev/impl/DevToys/UI/Controls/CodeEditor.xaml.cs

@@ -337,7 +337,8 @@ private void CopyButton_Click(object sender, RoutedEventArgs e)
             };
             data.SetText(Text ?? string.Empty);
 
-            Clipboard.SetContent(data);
+            Clipboard.SetContentWithOptions(data, new ClipboardContentOptions() { IsAllowedInHistory = true, IsRoamable = true });
+            Clipboard.Flush();
         }
 
         private async void OpenFileButton_Click(object sender, RoutedEventArgs e)

src/dev/impl/DevToys/UI/Controls/CustomTextBox.xaml

@@ -100,7 +100,9 @@
             TextWrapping="{x:Bind AcceptsReturn, Mode=OneWay, Converter={StaticResource BooleanToTextWrappingConverter}}"
             IsReadOnly="{x:Bind IsReadOnly, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
             AcceptsReturn="{x:Bind AcceptsReturn, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
-            Text="{x:Bind Text, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
+            Text="{x:Bind Text, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
+            CopyingToClipboard="TextBox_CopyingToClipboard"
+            CuttingToClipboard="TextBox_CuttingToClipboard"/>
         <RichEditBox
             x:Name="RichEditBox"
             x:Load="{x:Bind IsRichTextEdit}"
@@ -111,7 +113,9 @@
             IsSpellCheckEnabled="False"
             TextWrapping="{x:Bind AcceptsReturn, Mode=OneWay, Converter={StaticResource BooleanToTextWrappingConverter}}"
             IsReadOnly="{x:Bind IsReadOnly, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
-            AcceptsReturn="{x:Bind AcceptsReturn, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
+            AcceptsReturn="{x:Bind AcceptsReturn, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
+            CopyingToClipboard="RichEditBox_CopyingToClipboard"
+            CuttingToClipboard="RichEditBox_CuttingToClipboard">
             <RichEditBox.ContextFlyout>
                 <MenuFlyout>
                     <MenuFlyoutItem

src/dev/impl/DevToys/UI/Controls/CustomTextBox.xaml.cs

@@ -116,6 +116,7 @@ private bool CanExecuteCutCommand()
         private void ExecuteCutCommand()
         {
             RichEditBox.TextDocument.Selection.Cut();
+            Clipboard.Flush();
         }
 
         #endregion
@@ -132,6 +133,7 @@ private bool CanExecuteCopyCommand()
         private void ExecuteCopyCommand()
         {
             RichEditBox.TextDocument.Selection.Copy();
+            Clipboard.Flush();
         }
 
         #endregion
@@ -377,6 +379,23 @@ private RichEditBox GetRichEditBox()
             return (RichEditBox)(RichEditBox ?? FindName(nameof(RichEditBox)));
         }
 
+        private void CopyTextBoxSelectionToClipboard()
+        {
+            DataPackage dataPackage = new DataPackage { RequestedOperation = DataPackageOperation.Copy };
+            dataPackage.SetText(TextBox.SelectedText);
+            Clipboard.SetContentWithOptions(dataPackage, new ClipboardContentOptions() { IsAllowedInHistory = true, IsRoamable = true });
+            Clipboard.Flush(); // This method allows the content to remain available after the application shuts down.
+        }
+
+        private void CopyRichEditBoxSelectionToClipboard()
+        {
+            RichEditBox.Document.Selection.GetText(TextGetOptions.UseCrlf, out string text);
+            DataPackage dataPackage = new DataPackage { RequestedOperation = DataPackageOperation.Copy };
+            dataPackage.SetText(text);
+            Clipboard.SetContentWithOptions(dataPackage, new ClipboardContentOptions() { IsAllowedInHistory = true, IsRoamable = true });
+            Clipboard.Flush(); // This method allows the content to remain available after the application shuts down.
+        }
+
         private void OnLoaded(object sender, RoutedEventArgs e)
         {
             UpdateUI();
@@ -431,7 +450,8 @@ private void CopyButton_Click(object sender, RoutedEventArgs e)
             };
             data.SetText(Text);
 
-            Clipboard.SetContent(data);
+            Clipboard.SetContentWithOptions(data, new ClipboardContentOptions() { IsAllowedInHistory = true, IsRoamable = true });
+            Clipboard.Flush(); // This method allows the content to remain available after the application shuts down.
         }
 
         private async void OpenFileButton_Click(object sender, RoutedEventArgs e)
@@ -484,6 +504,30 @@ private void RichEditBox_TextChanging(RichEditBox sender, RichEditBoxTextChangin
             }
         }
 
+        private void TextBox_CopyingToClipboard(TextBox sender, TextControlCopyingToClipboardEventArgs args)
+        {
+            CopyTextBoxSelectionToClipboard();
+            args.Handled = true;
+        }
+
+        private void TextBox_CuttingToClipboard(TextBox sender, TextControlCuttingToClipboardEventArgs args)
+        {
+            CopyTextBoxSelectionToClipboard();
+            args.Handled = true;
+        }
+
+        private void RichEditBox_CopyingToClipboard(RichEditBox sender, TextControlCopyingToClipboardEventArgs args)
+        {
+            CopyRichEditBoxSelectionToClipboard();
+            args.Handled = true;
+        }
+
+        private void RichEditBox_CuttingToClipboard(RichEditBox sender, TextControlCuttingToClipboardEventArgs args)
+        {
+            CopyRichEditBoxSelectionToClipboard();
+            args.Handled = true;
+        }
+
         private void UserControl_SizeChanged(object sender, SizeChangedEventArgs e)
         {
             if (e.NewSize.Width < CommandsToolBar.ActualWidth + 100)

src/dev/impl/DevToys/ViewModels/Tools/Settings/SettingsToolViewModel.cs

@@ -140,7 +140,8 @@ private void ExecuteCopyVersionCommand()
             };
             data.SetText(Version);
 
-            Clipboard.SetContent(data);
+            Clipboard.SetContentWithOptions(data, new ClipboardContentOptions() { IsAllowedInHistory = true, IsRoamable = true });
+            Clipboard.Flush();
         }
 
         #endregion