HelpNavigator Enumeration
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HelpNavigator Enumeration


Specifies constants indicating which elements of the Help file to display.

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

public enum HelpNavigator

Member nameDescription

The Help file opens to the index entry for the first letter of a specified topic.


The Help file opens to the search page.


The Help file opens to the index.


The Help file opens to the topic with the specified index entry, if one exists; otherwise, the index entry closest to the specified keyword is displayed.


The Help file opens to the table of contents.


The Help file opens to a specified topic, if the topic exists.


The Help file opens to a topic indicated by a numeric topic identifier.

This enumeration is used by the Help and HelpProvider classes to provide access to specific elements of a Help file. For example, when used with the HelpProvider component that provides F1 Help, the TopicId or Topic value could be specified to open Help to a context-specific topic.

Legacy Code Example

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.

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);

.NET Framework
Available since 1.1
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