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Help Class

Encapsulates the HTML Help 1.0 engine.

For a list of all members of this type, see Help Members.


[Visual Basic]
Public Class Help
public class Help
public __gc class Help
public class Help

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.


You cannot create a new instance of the Help class. To provide Help to an application, call the static ShowHelp and ShowHelpIndex methods.

You can use the Help object to show compiled Help files (.chm) or HTML files in the HTML Help format. Compiled Help files provide table of contents, index, search, and keyword links in pages. Shortcuts work only in compiled Help files.

You can generate HTML Help 1.x files with the HTML Help Workshop. For more information on HTML Help, see the "HTML Help Workshop" or the other "HTML Help" topics in MSDN.


[Visual Basic, C#, C++] The following example displays a form with three buttons that can be used to interact with the mspaint.chm Help file. The Show Help Index button displays the Index tab for the Help file. The Show Help button displays content in the Help file based on the value selected in the Help Navigator list. The Show Keyword button displays content in the Help file based on the keyword specified in the Keyword text box.

[Visual Basic, C#, C++] For example, to show the Ovals Help page by the index value, select the HelpNavigator.KeywordIndex value in the Help Navigator drop-down list, type ovals (without the quotation marks) in the Parameter text box, and click the Show Help button. To show the To paint with a brush Help topic by the keyword, type mspaint.chm::/paint_brush.htm (without the quotation marks) in the Keyword text box and click the Show Keyword button.

[Visual Basic, C#, C++] The example uses the ShowHelp method to display the different Help tabs and Help topics, and the ShowHelpIndex method to display the Help index.

[Visual Basic] 
Imports System
Imports System.Drawing
Imports System.ComponentModel
Imports System.Windows.Forms

Public Class Form1
    Inherits System.Windows.Forms.Form
    Private helpfile As String = "mspaint.chm"
    Private WithEvents showIndex As System.Windows.Forms.Button
    Private WithEvents showHelp As System.Windows.Forms.Button
    Private WithEvents label1 As System.Windows.Forms.Label
    Private WithEvents navigatorCombo As System.Windows.Forms.ComboBox
    Private WithEvents showKeyword As System.Windows.Forms.Button
    Private WithEvents keyword As System.Windows.Forms.TextBox
    Private WithEvents label2 As System.Windows.Forms.Label
    Private WithEvents label3 As System.Windows.Forms.Label
    Private WithEvents parameterTextBox As System.Windows.Forms.TextBox

    <STAThread()> _
    Shared Sub Main()
        Application.Run(New Form1)
    End Sub 'Main
    Public Sub New()
        Me.showIndex = New System.Windows.Forms.Button
        Me.showHelp = New System.Windows.Forms.Button
        Me.navigatorCombo = New System.Windows.Forms.ComboBox
        Me.label1 = New System.Windows.Forms.Label
        Me.showKeyword = New System.Windows.Forms.Button
        Me.keyword = New System.Windows.Forms.TextBox
        Me.label2 = New System.Windows.Forms.Label
        Me.label3 = New System.Windows.Forms.Label
        Me.parameterTextBox = New System.Windows.Forms.TextBox

        ' Help Navigator Label
        Me.label1.Location = New System.Drawing.Point(112, 64)
        Me.label1.Size = New System.Drawing.Size(168, 16)
        Me.label1.Text = "Help Navigator:"

        ' Keyword Label
        Me.label2.Location = New System.Drawing.Point(120, 184)
        Me.label2.Size = New System.Drawing.Size(100, 16)
        Me.label2.Text = "Keyword:"

        ' Parameter Label
        Me.label3.Location = New System.Drawing.Point(112, 120)
        Me.label3.Size = New System.Drawing.Size(168, 16)
        Me.label3.Text = "Parameter:"

        ' Show Index Button
        Me.showIndex.Location = New System.Drawing.Point(16, 16)
        Me.showIndex.Size = New System.Drawing.Size(264, 32)
        Me.showIndex.TabIndex = 0
        Me.showIndex.Text = "Show Help Index"

        ' Show Help Button
        Me.showHelp.Location = New System.Drawing.Point(16, 80)
        Me.showHelp.Size = New System.Drawing.Size(80, 80)
        Me.showHelp.TabIndex = 1
        Me.showHelp.Text = "Show Help"

        ' Show Keyword Button
        Me.showKeyword.Location = New System.Drawing.Point(16, 192)
        Me.showKeyword.Size = New System.Drawing.Size(88, 32)
        Me.showKeyword.TabIndex = 4
        Me.showKeyword.Text = "Show Keyword"

        ' Help Navigator Combo
        Me.navigatorCombo.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList
        Me.navigatorCombo.Location = New System.Drawing.Point(112, 80)
        Me.navigatorCombo.Size = New System.Drawing.Size(168, 21)
        Me.navigatorCombo.TabIndex = 2

        ' Keyword TextBox
        Me.keyword.Location = New System.Drawing.Point(120, 200)
        Me.keyword.Size = New System.Drawing.Size(160, 20)
        Me.keyword.TabIndex = 5
        Me.keyword.Text = ""
        ' Parameter TextBox
        Me.parameterTextBox.Location = New System.Drawing.Point(112, 136)
        Me.parameterTextBox.Size = New System.Drawing.Size(168, 20)
        Me.parameterTextBox.TabIndex = 8
        Me.parameterTextBox.Text = ""

        ' Set up how the form should be displayed and add the controls to the form.
        Me.ClientSize = New System.Drawing.Size(292, 266)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.parameterTextBox, _
                                Me.label3, Me.label2, Me.keyword, Me.showKeyword, _
                                Me.label1, Me.navigatorCombo, Me.showHelp, Me.showIndex})
        Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog
        Me.Text = "Help App"

        ' Load the various values of the HelpNavigator enumeration
        ' into the combo box. 
        Dim converter As TypeConverter
        converter = TypeDescriptor.GetConverter(GetType(HelpNavigator))

        Dim value As Object
        For Each value In converter.GetStandardValues()
        Next value
    End Sub 'New

    Private Sub showIndex_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles showIndex.Click
        ' Display the index for the Help file.
        Help.ShowHelpIndex(Me, helpfile)
    End Sub 'showIndex_Click
    Private Sub showHelp_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles showHelp.Click
        ' Display Help using the Help navigator enumeration
        ' that is selected in the combo box. Some enumeration
        ' values make use of an extra parameter, which can
        ' be passed in through the Parameter text box.
        Dim navigator As HelpNavigator = HelpNavigator.TableOfContents
        If Not (navigatorCombo.SelectedItem Is Nothing) Then
            navigator = CType(navigatorCombo.SelectedItem, HelpNavigator)
        End If
        Help.ShowHelp(Me, helpfile, navigator, parameterTextBox.Text)
    End Sub 'showHelp_Click
    Private Sub showKeyword_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles showKeyword.Click
        ' Display Help using the provided keyword. 
        Help.ShowHelp(Me, helpfile, keyword.Text)
    End Sub 'showKeyword_Click
End Class 'Form1

using System;
using System.Drawing;
using System.ComponentModel;
using System.Windows.Forms;

public class Form1 : System.Windows.Forms.Form
    private const string helpfile = "mspaint.chm";
    private System.Windows.Forms.Button showIndex;
    private System.Windows.Forms.Button showHelp;
    private System.Windows.Forms.Label label1;
    private System.Windows.Forms.ComboBox navigatorCombo;
    private System.Windows.Forms.Button showKeyword;
    private System.Windows.Forms.TextBox keyword;
    private System.Windows.Forms.Label label2;
    private System.Windows.Forms.Label label3;
    private System.Windows.Forms.TextBox parameterTextBox;

    static void Main() 
        Application.Run(new Form1());

    public Form1()
        this.showIndex = new System.Windows.Forms.Button();
        this.showHelp = new System.Windows.Forms.Button();
        this.navigatorCombo = new System.Windows.Forms.ComboBox();
        this.label1 = new System.Windows.Forms.Label();
        this.showKeyword = new System.Windows.Forms.Button();
        this.keyword = new System.Windows.Forms.TextBox();
        this.label2 = new System.Windows.Forms.Label();
        this.label3 = new System.Windows.Forms.Label();
        this.parameterTextBox = new System.Windows.Forms.TextBox();

        // Help Navigator Label
        this.label1.Location = new System.Drawing.Point(112, 64);
        this.label1.Size = new System.Drawing.Size(168, 16);
        this.label1.Text = "Help Navigator:";

        // Keyword Label
        this.label2.Location = new System.Drawing.Point(120, 184);
        this.label2.Size = new System.Drawing.Size(100, 16);
        this.label2.Text = "Keyword:";

        // Parameter Label
        this.label3.Location = new System.Drawing.Point(112, 120);
        this.label3.Size = new System.Drawing.Size(168, 16);
        this.label3.Text = "Parameter:";

        // Show Index Button
        this.showIndex.Location = new System.Drawing.Point(16, 16);
        this.showIndex.Size = new System.Drawing.Size(264, 32);
        this.showIndex.TabIndex = 0;
        this.showIndex.Text = "Show Help Index";
        this.showIndex.Click += new System.EventHandler(this.showIndex_Click);

        // Show Help Button
        this.showHelp.Location = new System.Drawing.Point(16, 80);
        this.showHelp.Size = new System.Drawing.Size(80, 80);
        this.showHelp.TabIndex = 1;
        this.showHelp.Text = "Show Help";
        this.showHelp.Click += new System.EventHandler(this.showHelp_Click);

        // Show Keyword Button
        this.showKeyword.Location = new System.Drawing.Point(16, 192);
        this.showKeyword.Size = new System.Drawing.Size(88, 32);
        this.showKeyword.TabIndex = 4;
        this.showKeyword.Text = "Show Keyword";
        this.showKeyword.Click += new System.EventHandler(this.showKeyword_Click);

        // Help Navigator ComboBox
        this.navigatorCombo.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
        this.navigatorCombo.Location = new System.Drawing.Point(112, 80);
        this.navigatorCombo.Size = new System.Drawing.Size(168, 21);
        this.navigatorCombo.TabIndex = 2;

        // Keyword TextBox
        this.keyword.Location = new System.Drawing.Point(120, 200);
        this.keyword.Size = new System.Drawing.Size(160, 20);
        this.keyword.TabIndex = 5;
        this.keyword.Text = "";

        // Parameter TextBox
        this.parameterTextBox.Location = new System.Drawing.Point(112, 136);
        this.parameterTextBox.Size = new System.Drawing.Size(168, 20);
        this.parameterTextBox.TabIndex = 8;
        this.parameterTextBox.Text = "";

        // Set up how the form should be displayed and add the controls to the form.
        this.ClientSize = new System.Drawing.Size(292, 266);
        this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                        this.parameterTextBox, this.label3,
                                        this.label2, this.keyword,
                                        this.showKeyword, this.label1,
                                        this.navigatorCombo, this.showHelp,
        this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
        this.Text = "Help App";

        // Load the various values of the HelpNavigator enumeration
        // into the combo box.
        TypeConverter converter;
        converter = TypeDescriptor.GetConverter(typeof(HelpNavigator));
        foreach(object value in converter.GetStandardValues()) 

    private void showIndex_Click(object sender, System.EventArgs e)
        // Display the index for the help file.
        Help.ShowHelpIndex(this, helpfile);
    private void showHelp_Click(object sender, System.EventArgs e)
        // Display Help using the Help navigator enumeration
        // that is selected in the combo box. Some enumeration
        // values make use of an extra parameter, which can
        // be passed in through the Parameter text box.
        HelpNavigator navigator = HelpNavigator.TableOfContents;
        if (navigatorCombo.SelectedItem != null)
            navigator = (HelpNavigator)navigatorCombo.SelectedItem;
        Help.ShowHelp(this, helpfile, navigator, parameterTextBox.Text);
    private void showKeyword_Click(object sender, System.EventArgs e)
        // Display help using the provided keyword.
        Help.ShowHelp(this, helpfile, keyword.Text);

#using <mscorlib.dll>
#using <System.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::ComponentModel;
using namespace System::Windows::Forms;

public __gc class Form1 : public System::Windows::Forms::Form {
   String* helpfile;
   System::Windows::Forms::Button*  showIndex;
   System::Windows::Forms::Button*  showHelp;
   System::Windows::Forms::Label*  label1;
   System::Windows::Forms::ComboBox*  navigatorCombo;
   System::Windows::Forms::Button*  showKeyword;
   System::Windows::Forms::TextBox*  keyword;
   System::Windows::Forms::Label*  label2;
   System::Windows::Forms::Label*  label3;
   System::Windows::Forms::TextBox*  parameterTextBox;

   Form1() {

      helpfile = S"mspaint.chm";

      this->showIndex = new System::Windows::Forms::Button();
      this->showHelp = new System::Windows::Forms::Button();
      this->navigatorCombo = new System::Windows::Forms::ComboBox();
      this->label1 = new System::Windows::Forms::Label();
      this->showKeyword = new System::Windows::Forms::Button();
      this->keyword = new System::Windows::Forms::TextBox();
      this->label2 = new System::Windows::Forms::Label();
      this->label3 = new System::Windows::Forms::Label();
      this->parameterTextBox = new System::Windows::Forms::TextBox();

      // Help Navigator Label
      this->label1->Location = System::Drawing::Point(112, 64);
      this->label1->Size = System::Drawing::Size(168, 16);
      this->label1->Text = S"Help Navigator:";

      // Keyword Label 
      this->label2->Location = System::Drawing::Point(120, 184);
      this->label2->Size = System::Drawing::Size(100, 16);
      this->label2->Text = S"Keyword:";

      // Parameter Label
      this->label3->Location = System::Drawing::Point(112, 120);
      this->label3->Size = System::Drawing::Size(168, 16);
      this->label3->Text = S"Parameter:";

      // Show Index Button
      this->showIndex->Location = System::Drawing::Point(16, 16);
      this->showIndex->Size = System::Drawing::Size(264, 32);
      this->showIndex->TabIndex = 0;
      this->showIndex->Text = S"Show Help Index";
      this->showIndex->Click += new System::EventHandler(this, &Form1::showIndex_Click);

      // Show Help Button
      this->showHelp->Location = System::Drawing::Point(16, 80);
      this->showHelp->Size = System::Drawing::Size(80, 80);
      this->showHelp->TabIndex = 1;
      this->showHelp->Text = S"Show Help";
      this->showHelp->Click += new System::EventHandler(this, &Form1::showHelp_Click);

      // Show Keyword Button
      this->showKeyword->Location = System::Drawing::Point(16, 192);
      this->showKeyword->Size = System::Drawing::Size(88, 32);
      this->showKeyword->TabIndex = 4;
      this->showKeyword->Text = S"Show Keyword";
      this->showKeyword->Click += new System::EventHandler(this, &Form1::showKeyword_Click);

      // Help Navigator ComboBox
      this->navigatorCombo->DropDownStyle = 
      this->navigatorCombo->Location = System::Drawing::Point(112, 80);
      this->navigatorCombo->Size = System::Drawing::Size(168, 21);
      this->navigatorCombo->TabIndex = 2;

      // Keyword TextBox
      this->keyword->Location = System::Drawing::Point(120, 200);
      this->keyword->Size = System::Drawing::Size(160, 20);
      this->keyword->TabIndex = 5;
      this->keyword->Text = S"";

      // Parameter TextBox
      this->parameterTextBox->Location = System::Drawing::Point(112, 136);
      this->parameterTextBox->Size = System::Drawing::Size(168, 20);
      this->parameterTextBox->TabIndex = 8;
      this->parameterTextBox->Text = S"";

      // Set up how the form should be displayed and add the controls to the form.
      this->ClientSize = System::Drawing::Size(292, 266);
      System::Windows::Forms::Control* formControls[] = {
         this->parameterTextBox, this->label3,
            this->label2, this->keyword,
            this->showKeyword, this->label1,
            this->navigatorCombo, this->showHelp,
      this->FormBorderStyle = 
      this->Text = S"Help App";

      // Load the various values of the HelpNavigator enumeration
      // into the combo box.
      TypeConverter* converter;
      converter = TypeDescriptor::GetConverter(__typeof(HelpNavigator));
      System::Collections::IEnumerator* myEnum = 
      while (myEnum->MoveNext()) {
         Object* value = __try_cast<Object*>(myEnum->Current);

   void showIndex_Click(Object* /*sender*/, System::EventArgs* /*e*/) {
      // Display the index for the help file.
      Help::ShowHelpIndex(this, helpfile);
   void showHelp_Click(Object* /*sender*/, System::EventArgs* /*e*/) {
      // Display Help using the Help navigator enumeration
      // that is selected in the combo box. Some enumeration
      // values make use of an extra parameter, which can
      // be passed in through the Parameter text box.
      HelpNavigator navigator = HelpNavigator::TableOfContents;
      if (navigatorCombo->SelectedItem != 0) {
         navigator = *__try_cast<__box HelpNavigator*>(navigatorCombo->SelectedItem);
      Help::ShowHelp(this, helpfile, navigator, parameterTextBox->Text);
   void showKeyword_Click(Object* /*sender*/, System::EventArgs* /*e*/) {
      // Display help using the provided keyword.
      Help::ShowHelp(this, helpfile, keyword->Text);

int main() {
   Application::Run(new Form1());

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.


Namespace: System.Windows.Forms

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

Assembly: System.Windows.Forms (in System.Windows.Forms.dll)

See Also

Help Members | System.Windows.Forms Namespace | HelpNavigator | HelpProvider