File: TextBoxTests.cs
Web Access
Project: src\src\System.Windows.Forms\tests\UnitTests\System.Windows.Forms.Tests.csproj (System.Windows.Forms.Tests)
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.ComponentModel;
using System.Drawing;
using Point = System.Drawing.Point;
using Size = System.Drawing.Size;
 
namespace System.Windows.Forms.Tests;
 
public partial class TextBoxTests
{
    private static readonly int s_preferredHeight = Control.DefaultFont.Height + SystemInformation.BorderSize.Height * 4 + 3;
 
    [WinFormsFact]
    public void TextBox_Ctor_Default()
    {
        using SubTextBox control = new();
        Assert.False(control.AcceptsReturn);
        Assert.False(control.AcceptsTab);
        Assert.Null(control.AccessibleDefaultActionDescription);
        Assert.Null(control.AccessibleDescription);
        Assert.Null(control.AccessibleName);
        Assert.Equal(AccessibleRole.Default, control.AccessibleRole);
        Assert.False(control.AllowDrop);
        Assert.Equal(AnchorStyles.Top | AnchorStyles.Left, control.Anchor);
        Assert.Empty(control.AutoCompleteCustomSource);
        Assert.Same(control.AutoCompleteCustomSource, control.AutoCompleteCustomSource);
        Assert.Equal(AutoCompleteMode.None, control.AutoCompleteMode);
        Assert.Equal(AutoCompleteSource.None, control.AutoCompleteSource);
        Assert.True(control.AutoSize);
        Assert.Equal(SystemColors.Window, control.BackColor);
        Assert.Null(control.BackgroundImage);
        Assert.Equal(ImageLayout.Tile, control.BackgroundImageLayout);
        Assert.Null(control.BindingContext);
        Assert.Equal(BorderStyle.Fixed3D, control.BorderStyle);
        Assert.Equal(control.PreferredHeight, control.Bottom);
        Assert.Equal(new Rectangle(0, 0, 100, control.PreferredHeight), control.Bounds);
        Assert.False(control.CanFocus);
        Assert.True(control.CanRaiseEvents);
        Assert.True(control.CanSelect);
        Assert.False(control.CanUndo);
        Assert.False(control.Capture);
        Assert.True(control.CausesValidation);
        Assert.Equal(CharacterCasing.Normal, control.CharacterCasing);
        Assert.Equal(new Size(96, control.PreferredHeight - 4), control.ClientSize);
        Assert.Equal(new Rectangle(0, 0, 96, control.PreferredHeight - 4), control.ClientRectangle);
        Assert.Null(control.Container);
        Assert.False(control.ContainsFocus);
        Assert.Null(control.ContextMenuStrip);
        Assert.Empty(control.Controls);
        Assert.Same(control.Controls, control.Controls);
        Assert.False(control.Created);
        Assert.Same(Cursors.IBeam, control.Cursor);
        Assert.Same(Cursors.IBeam, control.DefaultCursor);
        Assert.Equal(ImeMode.Inherit, control.DefaultImeMode);
        Assert.Equal(new Padding(3), control.DefaultMargin);
        Assert.Equal(Size.Empty, control.DefaultMaximumSize);
        Assert.Equal(Size.Empty, control.DefaultMinimumSize);
        Assert.Equal(Padding.Empty, control.DefaultPadding);
        Assert.Equal(new Size(100, control.PreferredHeight), control.DefaultSize);
        Assert.False(control.DesignMode);
        Assert.Equal(new Rectangle(0, 0, 96, control.PreferredHeight - 4), control.DisplayRectangle);
        Assert.Equal(DockStyle.None, control.Dock);
        Assert.False(control.DoubleBuffered);
        Assert.True(control.Enabled);
        Assert.NotNull(control.Events);
        Assert.Same(control.Events, control.Events);
        Assert.False(control.Focused);
        Assert.Equal(Control.DefaultFont, control.Font);
        Assert.Equal(control.Font.Height, control.FontHeight);
        Assert.Equal(SystemColors.WindowText, control.ForeColor);
        Assert.False(control.HasChildren);
        Assert.Equal(control.PreferredHeight, control.Height);
        Assert.True(control.HideSelection);
        Assert.False(control.IsAccessible);
        Assert.False(control.IsMirrored);
        Assert.NotNull(control.LayoutEngine);
        Assert.Same(control.LayoutEngine, control.LayoutEngine);
        Assert.Equal(0, control.Left);
        Assert.Empty(control.Lines);
        Assert.Equal(Point.Empty, control.Location);
        Assert.Equal(new Padding(3), control.Margin);
        Assert.Equal(Size.Empty, control.MaximumSize);
        Assert.Equal(32767, control.MaxLength);
        Assert.Equal(Size.Empty, control.MinimumSize);
        Assert.False(control.Modified);
        Assert.False(control.Multiline);
        Assert.Equal(Padding.Empty, control.Padding);
        Assert.Null(control.Parent);
        Assert.Equal("Microsoft\u00AE .NET", control.ProductName);
        Assert.Equal(4, control.PreferredSize.Width);
        Assert.True(control.PreferredSize.Height > 0);
        Assert.True(control.PreferredHeight > 0);
        Assert.False(control.ReadOnly);
        Assert.False(control.RecreatingHandle);
        Assert.Null(control.Region);
        Assert.False(control.ResizeRedraw);
        Assert.Equal(100, control.Right);
        Assert.Equal(RightToLeft.No, control.RightToLeft);
        Assert.Equal(ScrollBars.None, control.ScrollBars);
        Assert.Empty(control.SelectedText);
        Assert.Equal(0, control.SelectionLength);
        Assert.Equal(0, control.SelectionStart);
        Assert.True(control.ShortcutsEnabled);
        Assert.True(control.ShowFocusCues);
        Assert.True(control.ShowKeyboardCues);
        Assert.Null(control.Site);
        Assert.Equal(new Size(100, control.PreferredHeight), control.Size);
        Assert.Equal(0, control.TabIndex);
        Assert.True(control.TabStop);
        Assert.Empty(control.Text);
        Assert.Equal(HorizontalAlignment.Left, control.TextAlign);
        Assert.Equal(0, control.TextLength);
        Assert.Equal(0, control.Top);
        Assert.Null(control.TopLevelControl);
        Assert.False(control.UseSystemPasswordChar);
        Assert.False(control.UseWaitCursor);
        Assert.True(control.Visible);
        Assert.Equal(100, control.Width);
        Assert.True(control.WordWrap);
 
        Assert.False(control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_CreateParams_GetDefault_ReturnsExpected()
    {
        using SubTextBox control = new();
        CreateParams createParams = control.CreateParams;
        Assert.Null(createParams.Caption);
        Assert.Equal("Edit", createParams.ClassName);
        Assert.Equal(0x8, createParams.ClassStyle);
        Assert.Equal(0x200, createParams.ExStyle);
        Assert.Equal(control.PreferredHeight, createParams.Height);
        Assert.Equal(IntPtr.Zero, createParams.Parent);
        Assert.Null(createParams.Param);
        Assert.Equal(0x560100C0, createParams.Style);
        Assert.Equal(100, createParams.Width);
        Assert.Equal(0, createParams.X);
        Assert.Equal(0, createParams.Y);
        Assert.Same(createParams, control.CreateParams);
        Assert.False(control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_CanEnableIme_GetWithoutHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.True(control.CanEnableIme);
        Assert.True(control.IsHandleCreated);
 
        // Get again.
        Assert.True(control.CanEnableIme);
        Assert.True(control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_CanEnableIme_GetWithHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.NotEqual(IntPtr.Zero, control.Handle);
        int invalidatedCallCount = 0;
        control.Invalidated += (sender, e) => invalidatedCallCount++;
        int styleChangedCallCount = 0;
        control.StyleChanged += (sender, e) => styleChangedCallCount++;
        int createdCallCount = 0;
        control.HandleCreated += (sender, e) => createdCallCount++;
 
        Assert.True(control.CanEnableIme);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
 
        // Get again.
        Assert.True(control.CanEnableIme);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
    }
 
    [WinFormsFact]
    public void TextBox_ImeMode_GetWithoutHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.Equal(ImeMode.NoControl, control.ImeMode);
        Assert.True(control.IsHandleCreated);
 
        // Get again.
        Assert.Equal(ImeMode.NoControl, control.ImeMode);
        Assert.True(control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_ImeMode_GetWithHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.NotEqual(IntPtr.Zero, control.Handle);
        int invalidatedCallCount = 0;
        control.Invalidated += (sender, e) => invalidatedCallCount++;
        int styleChangedCallCount = 0;
        control.StyleChanged += (sender, e) => styleChangedCallCount++;
        int createdCallCount = 0;
        control.HandleCreated += (sender, e) => createdCallCount++;
 
        Assert.Equal(ImeMode.NoControl, control.ImeMode);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
 
        // Get again.
        Assert.Equal(ImeMode.NoControl, control.ImeMode);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
    }
 
    [WinFormsFact]
    public void TextBox_ImeModeBase_GetWithoutHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.Equal(ImeMode.NoControl, control.ImeModeBase);
        Assert.True(control.IsHandleCreated);
 
        // Get again.
        Assert.Equal(ImeMode.NoControl, control.ImeModeBase);
        Assert.True(control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_ImeModeBase_GetWithHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.NotEqual(IntPtr.Zero, control.Handle);
        int invalidatedCallCount = 0;
        control.Invalidated += (sender, e) => invalidatedCallCount++;
        int styleChangedCallCount = 0;
        control.StyleChanged += (sender, e) => styleChangedCallCount++;
        int createdCallCount = 0;
        control.HandleCreated += (sender, e) => createdCallCount++;
 
        Assert.Equal(ImeMode.NoControl, control.ImeModeBase);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
 
        // Get again.
        Assert.Equal(ImeMode.NoControl, control.ImeModeBase);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
    }
 
    [WinFormsTheory]
    [InvalidEnumData<AutoCompleteMode>]
    public void TextBox_AutoCompleteMode_SetInvalidValue_ThrowsInvalidEnumArgumentException(AutoCompleteMode value)
    {
        using SubTextBox control = new();
 
        Action act = () => control.AutoCompleteMode = value;
        act.Should().Throw<InvalidEnumArgumentException>().And.ParamName.Should().Be("value");
    }
 
    [WinFormsTheory]
    [EnumData<AutoCompleteSource>]
    public void TextBox_AutoCompleteSource_Set_GetReturnsExpected(AutoCompleteSource value)
    {
        using SubTextBox control = new()
        {
            AutoCompleteSource = value == AutoCompleteSource.ListItems ? AutoCompleteSource.None : value
        };
 
        if (value != AutoCompleteSource.ListItems)
        {
            control.AutoCompleteSource.Should().Be(value);
        }
    }
 
    [WinFormsTheory]
    [InvalidEnumData<AutoCompleteSource>]
    public void TextBox_AutoCompleteSource_InvalidAutoCompleteSource_ThrowsInvalidEnumArgumentException(AutoCompleteSource source)
    {
        using SubTextBox control = new();
 
        Action act = () => control.AutoCompleteSource = source;
        act.Should().Throw<InvalidEnumArgumentException>().And.ParamName.Should().Be("value");
    }
 
    [WinFormsFact]
    public void TextBox_PasswordChar_GetWithoutHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.Equal('\0', control.PasswordChar);
        Assert.True(control.IsHandleCreated);
 
        // Get again.
        Assert.Equal('\0', control.PasswordChar);
        Assert.True(control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_PasswordChar_GetWithHandle_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.NotEqual(IntPtr.Zero, control.Handle);
        int invalidatedCallCount = 0;
        control.Invalidated += (sender, e) => invalidatedCallCount++;
        int styleChangedCallCount = 0;
        control.StyleChanged += (sender, e) => styleChangedCallCount++;
        int createdCallCount = 0;
        control.HandleCreated += (sender, e) => createdCallCount++;
 
        Assert.Equal('\0', control.PasswordChar);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
 
        // Get again.
        Assert.Equal('\0', control.PasswordChar);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
    }
 
    [WinFormsFact]
    public void TextBox_PlaceholderText()
    {
        using TextBox tb = new()
        {
            PlaceholderText = "Enter your name"
        };
        Assert.False(string.IsNullOrEmpty(tb.PlaceholderText));
    }
 
    [WinFormsFact]
    public void TextBox_PlaceholderText_DefaultValue()
    {
        using TextBox tb = new();
        Assert.Equal(string.Empty, tb.PlaceholderText);
    }
 
    [WinFormsFact]
    public void TextBox_PlaceholderText_When_InAccessibility_Doesnot_Raise_TextChanged()
    {
        using SubTextBox tb = new();
        bool eventRaised = false;
        EventHandler handler = (o, e) => eventRaised = true;
        tb.TextChanged += handler;
        tb.CreateAccessibilityInstance();
        Assert.False(eventRaised);
        tb.TextChanged -= handler;
    }
 
    public static IEnumerable<object[]> TextBox_ShouldRenderPlaceHolderText_TestData()
    {
        // Test PlaceholderText
        yield return new object[] { null, /* isUserPaint */ false, /* isIsFocused */ false, /* textCount */ 0, /* expected */ false };
        yield return new object[] { "", /* isUserPaint */ false, /* isIsFocused */ false, /* textCount */ 0, /* expected */ false };
 
        // Test UserPaint
        yield return new object[] { "Text", /* isUserPaint */ true, /* isIsFocused */ false, /* textCount */ 0, /* expected */ false };
 
        // Test Focused
        yield return new object[] { "Text", /* isUserPaint */ false, /* isIsFocused */ true, /* textCount */ 0, /* expected */ false };
 
        // Test TextLength
        yield return new object[] { "Text", /* isUserPaint */ false, /* isIsFocused */ false, /* textCount */ 1, /* expected */ false };
 
        // Happy path
        yield return new object[] { "Text", /* isUserPaint */ false, /* isIsFocused */ false, /* textCount */ 0, /* expected */ true };
    }
 
    [WinFormsTheory]
    [MemberData(nameof(TextBox_ShouldRenderPlaceHolderText_TestData))]
    public void TextBox_ShouldRenderPlaceHolderText(string text, bool isUserPaint, bool isIsFocused, int textCount, bool expected)
    {
        using SubTextBox textBox = new() { PlaceholderText = text, IsUserPaint = isUserPaint, IsFocused = isIsFocused, TextCount = textCount };
 
        bool result = textBox.TestAccessor().Dynamic.ShouldRenderPlaceHolderText();
        Assert.Equal(expected, result);
    }
 
    [WinFormsFact]
    public void TextBox_PlaceholderText_NullValue_CoercedTo_StringEmpty()
    {
        using TextBox tb = new()
        {
            PlaceholderText = "Text"
        };
 
        tb.PlaceholderText = null;
        Assert.Equal(string.Empty, tb.PlaceholderText);
    }
 
    [WinFormsFact]
    public void TextBox_PlaceholderText_Overridden()
    {
        using SubTextBox tb = new();
 
        Assert.NotNull(tb);
    }
 
    [WinFormsFact]
    public void TextBox_PlaceholderTextAlignments()
    {
        using TextBox tb = new()
        {
            PlaceholderText = "Enter your name"
        };
 
        // Cover the Placeholder draw code path
        PInvokeCore.SendMessage(tb, PInvokeCore.WM_PAINT, (WPARAM)(BOOL)false);
        tb.TextAlign = HorizontalAlignment.Center;
        PInvokeCore.SendMessage(tb, PInvokeCore.WM_PAINT, (WPARAM)(BOOL)false);
        tb.TextAlign = HorizontalAlignment.Right;
        PInvokeCore.SendMessage(tb, PInvokeCore.WM_PAINT, (WPARAM)(BOOL)false);
 
        Assert.False(string.IsNullOrEmpty(tb.PlaceholderText));
    }
 
    [WinFormsFact]
    public void TextBox_PlaceholderTextAlignmentsInRightToLeft()
    {
        using TextBox tb = new()
        {
            PlaceholderText = "Enter your name",
            RightToLeft = RightToLeft.Yes
        };
 
        // Cover the Placeholder draw code path in RightToLeft scenario
        PInvokeCore.SendMessage(tb, PInvokeCore.WM_PAINT, (WPARAM)(BOOL)false);
        tb.TextAlign = HorizontalAlignment.Center;
        PInvokeCore.SendMessage(tb, PInvokeCore.WM_PAINT, (WPARAM)(BOOL)false);
        tb.TextAlign = HorizontalAlignment.Right;
        PInvokeCore.SendMessage(tb, PInvokeCore.WM_PAINT, (WPARAM)(BOOL)false);
 
        Assert.False(string.IsNullOrEmpty(tb.PlaceholderText));
    }
 
    [WinFormsTheory]
    [InlineData(true, AccessibleRole.Text)]
    [InlineData(false, AccessibleRole.None)]
    public void TextBox_CreateAccessibilityInstance_Invoke_ReturnsExpected(bool createControl, AccessibleRole expectedAccessibleRole)
    {
        using SubTextBox control = new();
        if (createControl)
        {
            control.CreateControl();
        }
 
        Assert.Equal(createControl, control.IsHandleCreated);
        Control.ControlAccessibleObject instance = Assert.IsType<TextBox.TextBoxAccessibleObject>(control.CreateAccessibilityInstance());
        Assert.Equal(createControl, control.IsHandleCreated);
        Assert.NotNull(instance);
        Assert.Same(control, instance.Owner);
        Assert.Equal(expectedAccessibleRole, instance.Role);
        Assert.NotSame(control.CreateAccessibilityInstance(), instance);
        Assert.NotSame(control.AccessibilityObject, instance);
        Assert.Equal(createControl, control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_CreateAccessibilityInstance_InvokeWithCustomRole_ReturnsExpected()
    {
        using SubTextBox control = new()
        {
            AccessibleRole = AccessibleRole.HelpBalloon
        };
        Control.ControlAccessibleObject instance = Assert.IsType<TextBox.TextBoxAccessibleObject>(control.CreateAccessibilityInstance());
        Assert.NotNull(instance);
        Assert.Same(control, instance.Owner);
        Assert.Equal(AccessibleRole.HelpBalloon, instance.Role);
        Assert.NotSame(control.CreateAccessibilityInstance(), instance);
        Assert.NotSame(control.AccessibilityObject, instance);
        Assert.False(control.IsHandleCreated);
    }
 
    [WinFormsFact]
    public void TextBox_GetAutoSizeMode_Invoke_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.Equal(AutoSizeMode.GrowOnly, control.GetAutoSizeMode());
    }
 
    [WinFormsTheory]
    [InlineData(ControlStyles.ContainerControl, false)]
    [InlineData(ControlStyles.UserPaint, false)]
    [InlineData(ControlStyles.Opaque, false)]
    [InlineData(ControlStyles.ResizeRedraw, false)]
    [InlineData(ControlStyles.FixedWidth, false)]
    [InlineData(ControlStyles.FixedHeight, true)]
    [InlineData(ControlStyles.StandardClick, false)]
    [InlineData(ControlStyles.Selectable, true)]
    [InlineData(ControlStyles.UserMouse, false)]
    [InlineData(ControlStyles.SupportsTransparentBackColor, false)]
    [InlineData(ControlStyles.StandardDoubleClick, false)]
    [InlineData(ControlStyles.AllPaintingInWmPaint, true)]
    [InlineData(ControlStyles.CacheText, false)]
    [InlineData(ControlStyles.EnableNotifyMessage, false)]
    [InlineData(ControlStyles.DoubleBuffer, false)]
    [InlineData(ControlStyles.OptimizedDoubleBuffer, false)]
    [InlineData(ControlStyles.UseTextForAccessibility, false)]
    [InlineData((ControlStyles)0, true)]
    [InlineData((ControlStyles)int.MaxValue, false)]
    [InlineData((ControlStyles)(-1), false)]
    public void TextBox_GetStyle_Invoke_ReturnsExpected(ControlStyles flag, bool expected)
    {
        using SubTextBox control = new();
        Assert.Equal(expected, control.GetStyle(flag));
 
        // Call again to test caching.
        Assert.Equal(expected, control.GetStyle(flag));
    }
 
    [WinFormsFact]
    public void TextBox_GetTopLevel_Invoke_ReturnsExpected()
    {
        using SubTextBox control = new();
        Assert.False(control.GetTopLevel());
    }
 
    [WinFormsTheory]
    [NewAndDefaultData<EventArgs>]
    public void TextBox_OnHandleCreated_Invoke_CallsHandleCreated(EventArgs eventArgs)
    {
        using SubTextBox control = new();
        int callCount = 0;
        EventHandler handler = (sender, e) =>
        {
            Assert.Same(control, sender);
            Assert.Same(eventArgs, e);
            callCount++;
        };
 
        // Call with handler.
        control.HandleCreated += handler;
        control.OnHandleCreated(eventArgs);
        Assert.Equal(1, callCount);
        Assert.Equal(s_preferredHeight, control.Height);
        Assert.False(control.IsHandleCreated);
 
        // Remove handler.
        control.HandleCreated -= handler;
        control.OnHandleCreated(eventArgs);
        Assert.Equal(1, callCount);
        Assert.Equal(s_preferredHeight, control.Height);
        Assert.False(control.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [NewAndDefaultData<EventArgs>]
    public void TextBox_OnHandleCreated_InvokeWithHandle_CallsHandleCreated(EventArgs eventArgs)
    {
        using SubTextBox control = new();
        Assert.NotEqual(IntPtr.Zero, control.Handle);
        int callCount = 0;
        EventHandler handler = (sender, e) =>
        {
            Assert.Same(control, sender);
            Assert.Same(eventArgs, e);
            callCount++;
        };
 
        // Call with handler.
        control.HandleCreated += handler;
        control.OnHandleCreated(eventArgs);
        Assert.Equal(1, callCount);
        Assert.Equal(s_preferredHeight, control.Height);
        Assert.True(control.IsHandleCreated);
 
        // Remove handler.
        control.HandleCreated -= handler;
        control.OnHandleCreated(eventArgs);
        Assert.Equal(1, callCount);
        Assert.Equal(s_preferredHeight, control.Height);
        Assert.True(control.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [NewAndDefaultData<EventArgs>]
    public void TextBox_OnHandleDestroyed_Invoke_CallsHandleDestroyed(EventArgs eventArgs)
    {
        using SubTextBox control = new();
        int callCount = 0;
        EventHandler handler = (sender, e) =>
        {
            Assert.Same(control, sender);
            Assert.Same(eventArgs, e);
            callCount++;
        };
 
        // Call with handler.
        control.HandleDestroyed += handler;
        control.OnHandleDestroyed(eventArgs);
        Assert.Equal(1, callCount);
        Assert.False(control.IsHandleCreated);
 
        // Remove handler.
        control.HandleDestroyed -= handler;
        control.OnHandleDestroyed(eventArgs);
        Assert.Equal(1, callCount);
        Assert.False(control.IsHandleCreated);
    }
 
    public static IEnumerable<object[]> OnHandleDestroyed_TestData()
    {
        foreach (bool modified in new bool[] { true, false })
        {
            yield return new object[] { modified, null };
            yield return new object[] { modified, new EventArgs() };
        }
    }
 
    [WinFormsTheory]
    [MemberData(nameof(OnHandleDestroyed_TestData))]
    public void TextBox_OnHandleDestroyed_InvokeWithHandle_CallsHandleDestroyed(bool modified, EventArgs eventArgs)
    {
        using SubTextBox control = new()
        {
            Text = "Text",
            SelectionStart = 1,
            SelectionLength = 2,
            Modified = modified
        };
        Assert.NotEqual(IntPtr.Zero, control.Handle);
        int invalidatedCallCount = 0;
        control.Invalidated += (sender, e) => invalidatedCallCount++;
        int styleChangedCallCount = 0;
        control.StyleChanged += (sender, e) => styleChangedCallCount++;
        int createdCallCount = 0;
        control.HandleCreated += (sender, e) => createdCallCount++;
        int callCount = 0;
        EventHandler handler = (sender, e) =>
        {
            Assert.Same(control, sender);
            Assert.Same(eventArgs, e);
            callCount++;
        };
 
        // Call with handler.
        control.HandleDestroyed += handler;
        control.OnHandleDestroyed(eventArgs);
        Assert.Equal(1, callCount);
        Assert.Equal(s_preferredHeight, control.Height);
        Assert.Equal(0, control.SelectionStart);
        Assert.Equal(0, control.SelectionLength);
        Assert.Equal(modified, control.Modified);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
 
        // Remove handler.
        control.HandleDestroyed -= handler;
        control.OnHandleDestroyed(eventArgs);
        Assert.Equal(1, callCount);
        Assert.Equal(s_preferredHeight, control.Height);
        Assert.Equal(0, control.SelectionStart);
        Assert.Equal(0, control.SelectionLength);
        Assert.Equal(modified, control.Modified);
        Assert.True(control.IsHandleCreated);
        Assert.Equal(0, invalidatedCallCount);
        Assert.Equal(0, styleChangedCallCount);
        Assert.Equal(0, createdCallCount);
    }
 
    private class SubTextBox : TextBox
    {
        public int TextCount;
        public bool IsFocused;
        public bool TextAccessed;
 
        public new bool CanEnableIme => base.CanEnableIme;
 
        public new bool CanRaiseEvents => base.CanRaiseEvents;
 
        public new CreateParams CreateParams => base.CreateParams;
 
        public new Cursor DefaultCursor => base.DefaultCursor;
 
        public new ImeMode DefaultImeMode => base.DefaultImeMode;
 
        public new Padding DefaultMargin => base.DefaultMargin;
 
        public new Size DefaultMaximumSize => base.DefaultMaximumSize;
 
        public new Size DefaultMinimumSize => base.DefaultMinimumSize;
 
        public new Padding DefaultPadding => base.DefaultPadding;
 
        public new Size DefaultSize => base.DefaultSize;
 
        public new bool DesignMode => base.DesignMode;
 
        public new bool DoubleBuffered
        {
            get => base.DoubleBuffered;
            set => base.DoubleBuffered = value;
        }
 
        public new EventHandlerList Events => base.Events;
 
        public new int FontHeight
        {
            get => base.FontHeight;
            set => base.FontHeight = value;
        }
 
        public new ImeMode ImeModeBase
        {
            get => base.ImeModeBase;
            set => base.ImeModeBase = value;
        }
 
        public new bool IsHandleCreated => base.IsHandleCreated;
 
        public new bool ResizeRedraw
        {
            get => base.ResizeRedraw;
            set => base.ResizeRedraw = value;
        }
 
        public new bool ShowFocusCues => base.ShowFocusCues;
 
        public new bool ShowKeyboardCues => base.ShowKeyboardCues;
 
        public override string PlaceholderText { get => base.PlaceholderText; set => base.PlaceholderText = value; }
 
        public new AccessibleObject CreateAccessibilityInstance() => base.CreateAccessibilityInstance();
 
        public new AutoSizeMode GetAutoSizeMode() => base.GetAutoSizeMode();
 
        public new bool GetStyle(ControlStyles flag) => base.GetStyle(flag);
 
        public new bool GetTopLevel() => base.GetTopLevel();
 
        public override bool Focused => IsFocused;
        public override int TextLength => TextCount;
 
        public override string Text
        {
            get
            {
                TextAccessed = true;
                return base.Text;
            }
            set => base.Text = value;
        }
 
        public bool IsUserPaint
        {
            get => GetStyle(ControlStyles.UserPaint);
            set => SetStyle(ControlStyles.UserPaint, value);
        }
 
        public new void CreateControl() => base.CreateControl();
 
        public new void OnHandleCreated(EventArgs e) => base.OnHandleCreated(e);
 
        public new void OnHandleDestroyed(EventArgs e) => base.OnHandleDestroyed(e);
    }
}