File: TaskDialogSamples.cs
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Project: src\src\System.Windows.Forms\tests\IntegrationTests\WinformsControlsTest\WinformsControlsTest.csproj (WinFormsControlsTest)
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using Timer = System.Windows.Forms.Timer;
 
namespace WinFormsControlsTest;
 
[DesignerCategory("Default")]
public class TaskDialogSamples : Form
{
    public TaskDialogSamples()
    {
        Text = "Task Dialog Demos";
 
        AutoSize = true;
        AutoSizeMode = AutoSizeMode.GrowAndShrink;
        MinimizeBox = false;
        MaximizeBox = false;
 
        FlowLayoutPanel flowLayout = new()
        {
            Dock = DockStyle.Fill,
            FlowDirection = FlowDirection.TopDown,
            AutoSize = true,
            AutoSizeMode = AutoSizeMode.GrowAndShrink,
            Parent = this,
        };
 
        void AddButtonForAction(string name, Action action)
        {
            Button button = new()
            {
                Text = name,
                AutoSize = true,
                AutoSizeMode = AutoSizeMode.GrowAndShrink,
                Anchor = AnchorStyles.Left | AnchorStyles.Right,
            };
 
            button.Click += (s, e) => action();
 
            flowLayout.Controls.Add(button);
        }
 
        AddButtonForAction("Confirmation Dialog (3x)", ShowSimpleTaskDialog);
        AddButtonForAction("Close Document Confirmation", ShowCloseDocumentTaskDialog);
        AddButtonForAction("Minesweeper Difficulty", ShowMinesweeperDifficultySelectionTaskDialog);
        AddButtonForAction("Auto-Closing Dialog", ShowAutoClosingTaskDialog);
        AddButtonForAction("Multi-Page Dialog (modeless)", ShowMultiPageTaskDialog);
        AddButtonForAction("Elevation Required", ShowElevatedProcessTaskDialog);
        AddButtonForAction("Events Demo", ShowEventsDemoTaskDialog);
        AddButtonForAction("Hyperlinks Demo", ShowHyperlinksDemoTaskDialog);
    }
 
    private void ShowSimpleTaskDialog()
    {
        // Show a message box.
        DialogResult messageBoxResult = MessageBox.Show(
            this,
            text: "Stopping the operation might leave your database in a corrupted state. Are you sure you want to stop?",
            caption: "Confirmation [Message Box]",
            buttons: MessageBoxButtons.YesNo,
            icon: MessageBoxIcon.Warning,
            defaultButton: MessageBoxDefaultButton.Button2);
 
        if (messageBoxResult == DialogResult.Yes)
        {
            Console.WriteLine("User confirmed to stop the operation.");
        }
 
        // Show a task dialog (simple).
        TaskDialogButton result = TaskDialog.ShowDialog(this, new TaskDialogPage()
        {
            Text = "Stopping the operation might leave your database in a corrupted state.",
            Heading = "Are you sure you want to stop?",
            Caption = "Confirmation (Task Dialog)",
            Buttons =
            {
                TaskDialogButton.Yes,
                TaskDialogButton.No
            },
            Icon = TaskDialogIcon.Warning,
            DefaultButton = TaskDialogButton.No
        });
 
        if (result == TaskDialogButton.Yes)
        {
            Console.WriteLine("User confirmed to stop the operation.");
        }
 
        // Show a task dialog (enhanced).
        TaskDialogPage page = new()
        {
            Heading = "Are you sure you want to stop?",
            Text = "Stopping the operation might leave your database in a corrupted state.",
            Caption = "Confirmation (Task Dialog)",
            Icon = TaskDialogIcon.Warning,
            AllowCancel = true,
 
            Verification = new TaskDialogVerificationCheckBox()
            {
                Text = "Do not show again"
            },
 
            Buttons =
            {
                TaskDialogButton.Yes,
                TaskDialogButton.No
            },
 
            DefaultButton = TaskDialogButton.No
        };
 
        var resultButton = TaskDialog.ShowDialog(this, page);
 
        if (resultButton == TaskDialogButton.Yes)
        {
            if (page.Verification.Checked)
                Console.WriteLine("Do not show this confirmation again.");
 
            Console.WriteLine("User confirmed to stop the operation.");
        }
    }
 
    private void ShowCloseDocumentTaskDialog()
    {
        // Create the page which we want to show in the dialog.
        TaskDialogButton btnCancel = TaskDialogButton.Cancel;
        TaskDialogButton btnSave = new("&Save");
        TaskDialogButton btnDontSave = new("Do&n't save");
 
        TaskDialogPage page = new()
        {
            Caption = "My Application",
            Heading = "Do you want to save changes to Untitled?",
            Buttons =
            {
                btnCancel,
                btnSave,
                btnDontSave
            }
        };
 
        // Show a modal dialog, then check the result.
        TaskDialogButton result = TaskDialog.ShowDialog(this, page);
 
        if (result == btnSave)
            Console.WriteLine("Saving");
        else if (result == btnDontSave)
            Console.WriteLine("Not saving");
        else
            Console.WriteLine("Canceling");
    }
 
    private void ShowMinesweeperDifficultySelectionTaskDialog()
    {
        TaskDialogPage page = new()
        {
            Caption = "Minesweeper",
            Heading = "What level of difficulty do you want to play?",
            AllowCancel = true,
 
            Footnote = new TaskDialogFootnote()
            {
                Text = "Note: You can change the difficulty level later " +
                    "by clicking Options on the Game menu.",
            },
 
            Buttons =
            {
                new TaskDialogCommandLinkButton("&Beginner", "10 mines, 9 x 9 tile grid")
                {
                    Tag = 10
                },
                new TaskDialogCommandLinkButton("&Intermediate", "40 mines, 16 x 16 tile grid")
                {
                    Tag = 40
                },
                new TaskDialogCommandLinkButton("&Advanced", "99 mines, 16 x 30 tile grid")
                {
                    Tag = 99
                }
            }
        };
 
        TaskDialogButton result = TaskDialog.ShowDialog(this, page);
 
        if (result.Tag is int resultingMines)
            Console.WriteLine($"Playing with {resultingMines} mines...");
        else
            Console.WriteLine("User canceled.");
    }
 
    private void ShowAutoClosingTaskDialog()
    {
        int remainingTenthSeconds = 50;
 
        TaskDialogButton reconnectButton = new("&Reconnect now");
        var cancelButton = TaskDialogButton.Cancel;
 
        TaskDialogPage page = new()
        {
            Heading = "Connection lost; reconnecting...",
            Text = $"Reconnecting in {(remainingTenthSeconds + 9) / 10} seconds...",
            // Display the form's icon in the task dialog.
            // Note however that the task dialog will not scale the icon.
            Icon = new TaskDialogIcon(Icon),
            ProgressBar = new TaskDialogProgressBar()
            {
                State = TaskDialogProgressBarState.Paused
            },
            Buttons =
            {
                reconnectButton,
                cancelButton
            }
        };
 
        // Create a WinForms timer that raises the Tick event every tenth second.
        using Timer timer = new()
        {
            Enabled = true,
            Interval = 100
        };
 
        timer.Tick += (s, e) =>
        {
            remainingTenthSeconds--;
            if (remainingTenthSeconds > 0)
            {
                // Update the remaining time and progress bar.
                page.Text = $"Reconnecting in {(remainingTenthSeconds + 9) / 10} seconds...";
                page.ProgressBar.Value = 100 - remainingTenthSeconds * 2;
            }
            else
            {
                // Stop the timer and click the "Reconnect" button - this will
                // close the dialog.
                timer.Enabled = false;
                reconnectButton.PerformClick();
            }
        };
 
        TaskDialogButton result = TaskDialog.ShowDialog(this, page);
        if (result == reconnectButton)
            Console.WriteLine("Reconnecting.");
        else
            Console.WriteLine("Not reconnecting.");
    }
 
    private void ShowMultiPageTaskDialog()
    {
        // Disable the "Yes" button and only enable it when the check box is checked.
        // Also, don't close the dialog when this button is clicked.
        var initialButtonYes = TaskDialogButton.Yes;
        initialButtonYes.Enabled = false;
        initialButtonYes.AllowCloseDialog = false;
 
        TaskDialogPage initialPage = new()
        {
            Caption = "My Application",
            Heading = "Clean up database?",
            Text = "Do you really want to do a clean-up?\nThis action is irreversible!",
            Icon = TaskDialogIcon.ShieldWarningYellowBar,
            AllowCancel = true,
            // A modeless dialog can be minimizable.
            AllowMinimize = true,
 
            Verification = new TaskDialogVerificationCheckBox()
            {
                Text = "I know what I'm doing"
            },
 
            Buttons =
            {
                TaskDialogButton.No,
                initialButtonYes
            },
            DefaultButton = TaskDialogButton.No
        };
 
        // For the "In Progress" page, don't allow the dialog to close, by adding
        // a disabled button (if no button was specified, the task dialog would
        // get an (enabled) 'OK' button).
        var inProgressCloseButton = TaskDialogButton.Close;
        inProgressCloseButton.Enabled = false;
 
        TaskDialogPage inProgressPage = new()
        {
            Caption = "My Application",
            Heading = "Operation in progress...",
            Text = "Please wait while the operation is in progress.",
            Icon = TaskDialogIcon.Information,
            AllowMinimize = true,
 
            ProgressBar = new TaskDialogProgressBar()
            {
                State = TaskDialogProgressBarState.Marquee
            },
 
            Expander = new TaskDialogExpander()
            {
                Text = "Initializing...",
                Position = TaskDialogExpanderPosition.AfterFootnote
            },
 
            Buttons =
            {
                inProgressCloseButton
            }
        };
 
        // Add an invisible Cancel button where we will intercept the Click event
        // to prevent the dialog from closing (when the User clicks the "X" button
        // in the title bar or presses ESC or Alt+F4).
        var invisibleCancelButton = TaskDialogButton.Cancel;
        invisibleCancelButton.Visible = false;
        invisibleCancelButton.AllowCloseDialog = false;
        inProgressPage.Buttons.Add(invisibleCancelButton);
 
        TaskDialogPage finishedPage = new()
        {
            Caption = "My Application",
            Heading = "Success!",
            Text = "The operation finished.",
            Icon = TaskDialogIcon.ShieldSuccessGreenBar,
            AllowMinimize = true,
            Buttons =
            {
                TaskDialogButton.Close
            }
        };
 
        TaskDialogButton showResultsButton = new TaskDialogCommandLinkButton("Show &Results");
        finishedPage.Buttons.Add(showResultsButton);
 
        // Enable the "Yes" button only when the checkbox is checked.
        TaskDialogVerificationCheckBox checkBox = initialPage.Verification;
        checkBox.CheckedChanged += (sender, e) =>
        {
            initialButtonYes.Enabled = checkBox.Checked;
        };
 
        // When the user clicks "Yes", navigate to the second page.
        initialButtonYes.Click += (sender, e) =>
        {
            // Navigate to the "In Progress" page that displays the
            // current progress of the background work.
            initialPage.Navigate(inProgressPage);
 
            // NOTE: When you implement a "In Progress" page that represents
            // background work that is done e.g. by a separate thread/task,
            // which eventually calls Control.Invoke()/BeginInvoke() when
            // its work is finished in order to navigate or update the dialog,
            // then DO NOT start that work here already (directly after
            // setting the Page property). Instead, start the work in the
            // TaskDialogPage.Created event of the new page.
            //
            // See comments in the code sample in https://github.com/dotnet/winforms/issues/146
            // for more information.
        };
 
        // Simulate work by starting an async operation from which we are updating the
        // progress bar and the expander with the current status.
        inProgressPage.Created += async (s, e) =>
        {
            // Run the background operation and iterate over the streamed values to update
            // the progress. Because we call the async method from the GUI thread,
            // it will use this thread's synchronization context to run the continuations,
            // so we don't need to use Control.[Begin]Invoke() to schedule the callbacks.
            var progressBar = inProgressPage.ProgressBar;
 
            await foreach (int progressValue in StreamBackgroundOperationProgressAsync())
            {
                // When we display the first progress, switch the marquee progress bar
                // to a regular one.
                if (progressBar.State == TaskDialogProgressBarState.Marquee)
                    progressBar.State = TaskDialogProgressBarState.Normal;
 
                progressBar.Value = progressValue;
                inProgressPage.Expander.Text = $"Progress: {progressValue} %";
            }
 
            // Work is finished, so navigate to the third page.
            inProgressPage.Navigate(finishedPage);
        };
 
        // Show the dialog (modeless).
        TaskDialogButton result = TaskDialog.ShowDialog(initialPage);
        if (result == showResultsButton)
        {
            Console.WriteLine("Showing Results!");
        }
 
        static async IAsyncEnumerable<int> StreamBackgroundOperationProgressAsync()
        {
            // Note: The code here will run in the GUI thread - use
            // "await Task.Run(...)" to schedule CPU-intensive operations in a
            // worker thread.
 
            // Wait a bit before reporting the first progress.
            await Task.Delay(2800);
 
            for (int i = 0; i <= 100; i += 4)
            {
                // Report the progress.
                yield return i;
 
                // Wait a bit to simulate work.
                await Task.Delay(200);
            }
        }
    }
 
    private void ShowElevatedProcessTaskDialog()
    {
        TaskDialogPage page = new()
        {
            Heading = "Settings saved - Service Restart required",
            Text = "The service needs to be restarted to apply the changes.",
            Icon = TaskDialogIcon.ShieldSuccessGreenBar,
            Buttons =
            {
                TaskDialogButton.Close
            }
        };
 
        TaskDialogCommandLinkButton restartNowButton = new("&Restart now");
        page.Buttons.Add(restartNowButton);
 
        restartNowButton.ShowShieldIcon = true;
        restartNowButton.Click += (s, e) =>
        {
            restartNowButton.AllowCloseDialog = true;
            restartNowButton.Enabled = false;
 
            // Try to start an elevated cmd.exe.
            ProcessStartInfo psi = new("cmd.exe", "/k echo Hi, this is an elevated command prompt.")
            {
                UseShellExecute = true,
                Verb = "runas"
            };
 
            try
            {
                Process.Start(psi)?.Dispose();
            }
            catch (Win32Exception ex) when (ex.NativeErrorCode == 1223)
            {
                // The user canceled the UAC prompt, so don't close the dialog and
                // re-enable the restart button.
                restartNowButton.AllowCloseDialog = false;
                restartNowButton.Enabled = true;
                return;
            }
        };
 
        TaskDialog.ShowDialog(this, page);
    }
 
    private void ShowEventsDemoTaskDialog()
    {
        TaskDialogPage page1 = new()
        {
            Caption = Text,
            Heading = "Event Demo",
            Text = "Event Demo...",
        };
 
        page1.Created += (s, e) => Console.WriteLine("Page1 Created");
        page1.Destroyed += (s, e) => Console.WriteLine("Page1 Destroyed");
        page1.HelpRequest += (s, e) => Console.WriteLine("Page1 HelpRequest");
 
        page1.Expander = new TaskDialogExpander("Expander")
        {
            Position = TaskDialogExpanderPosition.AfterFootnote
        };
 
        page1.Expander.ExpandedChanged += (s, e) => Console.WriteLine($"Expander ExpandedChanged: {page1.Expander.Expanded}");
 
        var buttonOK = TaskDialogButton.OK;
        var buttonHelp = TaskDialogButton.Help;
        TaskDialogCommandLinkButton buttonCancelClose = new("C&ancel Close", allowCloseDialog: false);
        TaskDialogCommandLinkButton buttonShowInnerDialog = new("&Show (modeless) Inner Dialog", "(and don't cancel the Close)");
        TaskDialogCommandLinkButton buttonNavigate = new("&Navigate", allowCloseDialog: false);
 
        page1.Buttons.Add(buttonOK);
        page1.Buttons.Add(buttonHelp);
        page1.Buttons.Add(buttonCancelClose);
        page1.Buttons.Add(buttonShowInnerDialog);
        page1.Buttons.Add(buttonNavigate);
 
        buttonOK.Click += (s, e) => Console.WriteLine($"Button '{s}' Click");
        buttonHelp.Click += (s, e) => Console.WriteLine($"Button '{s}' Click");
 
        buttonCancelClose.Click += (s, e) =>
        {
            Console.WriteLine($"Button '{s}' Click");
        };
 
        buttonShowInnerDialog.Click += (s, e) =>
        {
            Console.WriteLine($"Button '{s}' Click");
            TaskDialog.ShowDialog(new TaskDialogPage()
            {
                Text = "Inner Dialog"
            });
            Console.WriteLine($"(returns) Button '{s}' Click");
        };
 
        buttonNavigate.Click += (s, e) =>
        {
            Console.WriteLine($"Button '{s}' Click");
 
            // Navigate to a new page.
            TaskDialogPage page2 = new()
            {
                Heading = "AfterNavigation.",
                Buttons =
                {
                    TaskDialogButton.Close
                }
            };
            page2.Created += (s, e) => Console.WriteLine("Page2 Created");
            page2.Destroyed += (s, e) => Console.WriteLine("Page2 Destroyed");
 
            page1.Navigate(page2);
        };
 
        page1.Verification = new TaskDialogVerificationCheckBox("&CheckBox");
        page1.Verification.CheckedChanged += (s, e) => Console.WriteLine($"CheckBox CheckedChanged: {page1.Verification.Checked}");
 
        var radioButton1 = page1.RadioButtons.Add("Radi&oButton 1");
        var radioButton2 = page1.RadioButtons.Add("RadioB&utton 2");
 
        radioButton1.CheckedChanged += (s, e) => Console.WriteLine($"RadioButton1 CheckedChanged: {radioButton1.Checked}");
        radioButton2.CheckedChanged += (s, e) => Console.WriteLine($"RadioButton2 CheckedChanged: {radioButton2.Checked}");
 
        var dialogResult = TaskDialog.ShowDialog(page1);
        Console.WriteLine($"---> Dialog Result: {dialogResult}");
    }
 
    private void ShowHyperlinksDemoTaskDialog()
    {
        TaskDialogPage page = new()
        {
            Caption = Text,
            Text = """<a href="Href 1">Link with accelerator &1</a> Text with literal '&&' <a href="Href 2">Link with accelerator &2</a>""",
            Footnote = new() { Text = """<a href="Href 3">Link with literal '&&'</a> Text with &accelerator""" },
            Expander = new() { Text = """<a href="Href 4">Link 4</a>""" },
            EnableLinks = true,
        };
 
        page.LinkClicked += (_, e) =>
        {
            page.Heading = "Clicked: " + e.LinkHref;
        };
 
        TaskDialog.ShowDialog(page);
    }
}