Trying to use the C# SpellCheck class

Question

I am trying to use the SpellCheck class C# provides (in PresentationFramework.dll). But, I am experiencing problems when trying to bind the spelling to my textbox:

SpellCheck.SetIsEnabled(txtWhatever, true); 

The problem is that my txtWhatever is of type System.Windows.Forms and the parameter this function is looking for is System.Windows.Controls, and simple converting failed. I also tried to make my TextBox of this type, but... couldn't. Does anyone know how to use this SpellCheck object? (MSDN wasn't that helpful...)

Thanks

Answer 1

You have to use a WPF TextBox to make spell checking work. You can embed one in a Windows Forms form with the ElementHost control. It works pretty similar to a UserControl. Here's a control that you can drop straight from the toolbox. To get started, you need Project + Add Reference and select WindowsFormsIntegration, System.Design and the WPF assemblies PresentationCore, PresentationFramework and WindowsBase.

Add a new class to your project and paste the code shown below. Compile. Drop the SpellBox control from the top of the toolbox onto a form. It supports the TextChanged event and the Multiline and WordWrap properties. There's a nagging problem with the Font, there is no easy way to map a WF Font to the WPF font properties. The easiest workaround for that is to set the form's Font to "Segoe UI", the default for WPF.

using System; using System.ComponentModel; using System.ComponentModel.Design.Serialization; using System.Windows; using System.Windows.Controls; using System.Windows.Forms.Integration; using System.Windows.Forms.Design;  [Designer(typeof(ControlDesigner))] //[DesignerSerializer("System.Windows.Forms.Design.ControlCodeDomSerializer, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", "System.ComponentModel.Design.Serialization.CodeDomSerializer, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")] class SpellBox : ElementHost {     public SpellBox() {         box = new TextBox();         base.Child = box;         box.TextChanged += (s, e) => OnTextChanged(EventArgs.Empty);         box.SpellCheck.IsEnabled = true;         box.VerticalScrollBarVisibility = ScrollBarVisibility.Auto;         this.Size = new System.Drawing.Size(100, 20);     }     public override string Text {         get { return box.Text; }         set { box.Text = value; }     }     [DefaultValue(false)]     public bool Multiline {         get { return box.AcceptsReturn; }         set { box.AcceptsReturn = value; }     }     [DefaultValue(false)]     public bool WordWrap {         get { return box.TextWrapping != TextWrapping.NoWrap; }         set { box.TextWrapping = value ? TextWrapping.Wrap : TextWrapping.NoWrap; }     }     [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]     public new System.Windows.UIElement Child {         get { return base.Child; }         set { /* Do nothing to solve a problem with the serializer !! */ }     }     private TextBox box; } 

By popular demand, a VB.NET version of this code that avoids the lambda:

Imports System Imports System.ComponentModel Imports System.ComponentModel.Design.Serialization Imports System.Windows Imports System.Windows.Controls Imports System.Windows.Forms.Integration Imports System.Windows.Forms.Design  <Designer(GetType(ControlDesigner))> _ Class SpellBox     Inherits ElementHost      Public Sub New()         box = New TextBox()         MyBase.Child = box         AddHandler box.TextChanged, AddressOf box_TextChanged         box.SpellCheck.IsEnabled = True         box.VerticalScrollBarVisibility = ScrollBarVisibility.Auto         Me.Size = New System.Drawing.Size(100, 20)     End Sub      Private Sub box_TextChanged(ByVal sender As Object, ByVal e As EventArgs)         OnTextChanged(EventArgs.Empty)     End Sub      Public Overrides Property Text() As String         Get             Return box.Text         End Get         Set(ByVal value As String)             box.Text = value         End Set     End Property      <DefaultValue(False)> _     Public Property MultiLine() As Boolean         Get             Return box.AcceptsReturn         End Get         Set(ByVal value As Boolean)             box.AcceptsReturn = value         End Set     End Property      <DefaultValue(False)> _     Public Property WordWrap() As Boolean         Get             Return box.TextWrapping <> TextWrapping.NoWrap         End Get         Set(ByVal value As Boolean)             If value Then                 box.TextWrapping = TextWrapping.Wrap             Else                 box.TextWrapping = TextWrapping.NoWrap             End If         End Set     End Property      <DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)> _     Public Shadows Property Child() As System.Windows.UIElement         Get             Return MyBase.Child         End Get         Set(ByVal value As System.Windows.UIElement)             '' Do nothing to solve a problem with the serializer !!         End Set     End Property     Private box As TextBox End Class