Help Class
Encapsulates the HTML Help 1.0 engine.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
You cannot create a new instance of the Help class. To provide Help for an application, call the static ShowHelp and ShowHelpIndex methods.
You can use Help 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 "HTML Help Workshop" and other HTML Help topics at http://msdn.microsoft.com.
The following code 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.
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 in the Parameter text box, and then click the Show Help button. To show the "To paint with a brush" Help topic by the keyword, type mspaint.chm::/paint_brush.htm in the Keyword text box, and then click the Show Keyword button.
The example uses the ShowHelp method to display the different Help tabs and Help topics, and the ShowHelpIndex method to display the Help index.
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() navigatorCombo.Items.Add(value) 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 (navigatorCombo.SelectedItem IsNot 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
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows Mobile for Pocket PC
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.