HelpProvider.SetShowHelp(Control, Boolean) Method

Definition

Specifies whether Help is displayed for the specified control.

public virtual void SetShowHelp (System.Windows.Forms.Control ctl, bool value);

Parameters

ctl
Control

A Control for which Help is turned on or off.

value
Boolean

true if Help displays for the control; otherwise, false.

Examples

The following code example demonstrates using the HelpProvider class to display context-sensitive Help on a form containing four address fields. The example uses the SetHelpString method to set the Help ToolTip text. When you use the context-sensitive Help button and click the Help cursor on an address field, the Help ToolTip appears with the specified text. When you press the F1 key with the focus in an address field, the mspaint.chm Help file is displayed because the HelpNamespace property has been set to mspaint.chm. The SetShowHelp method is called for each address control to identify that it has Help content available.

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

public class Form1 : System.Windows.Forms.Form
{
    private System.Windows.Forms.TextBox addressTextBox;
    private System.Windows.Forms.Label label2;
    private System.Windows.Forms.TextBox cityTextBox;
    private System.Windows.Forms.Label label3;
    private System.Windows.Forms.TextBox stateTextBox;
    private System.Windows.Forms.TextBox zipTextBox;
    private System.Windows.Forms.HelpProvider helpProvider1;
    private System.Windows.Forms.Label helpLabel;

    [STAThread]
    static void Main() 
    {
        Application.Run(new Form1());
    }

    public Form1()
    {
        this.addressTextBox = new System.Windows.Forms.TextBox();
        this.helpLabel = new System.Windows.Forms.Label();
        this.label2 = new System.Windows.Forms.Label();
        this.cityTextBox = new System.Windows.Forms.TextBox();
        this.label3 = new System.Windows.Forms.Label();
        this.stateTextBox = new System.Windows.Forms.TextBox();
        this.zipTextBox = new System.Windows.Forms.TextBox();
        
        // Help Label
        this.helpLabel.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
        this.helpLabel.Location = new System.Drawing.Point(8, 80);
        this.helpLabel.Size = new System.Drawing.Size(272, 72);
        this.helpLabel.Text = "Click the Help button in the title bar, then click a control " + 
            "to see a Help tooltip for the control.  Click on a control and press F1 to invoke " +
            "the Help system with a sample Help file.";

        // Address Label
        this.label2.Location = new System.Drawing.Point(16, 8);
        this.label2.Size = new System.Drawing.Size(100, 16);
        this.label2.Text = "Address:";

        // Comma Label
        this.label3.Location = new System.Drawing.Point(136, 56);
        this.label3.Size = new System.Drawing.Size(16, 16);
        this.label3.Text = ",";

        // Create the HelpProvider.
        this.helpProvider1 = new System.Windows.Forms.HelpProvider();

        // Tell the HelpProvider what controls to provide help for, and
        // what the help string is.
        this.helpProvider1.SetShowHelp(this.addressTextBox, true);
        this.helpProvider1.SetHelpString(this.addressTextBox, "Enter the street address in this text box.");

        this.helpProvider1.SetShowHelp(this.cityTextBox, true);
        this.helpProvider1.SetHelpString(this.cityTextBox, "Enter the city here.");

        this.helpProvider1.SetShowHelp(this.stateTextBox, true);
        this.helpProvider1.SetHelpString(this.stateTextBox, "Enter the state in this text box.");

        this.helpProvider1.SetShowHelp(this.zipTextBox, true);
        this.helpProvider1.SetHelpString(this.zipTextBox, "Enter the zip code here.");

        // Set what the Help file will be for the HelpProvider.
        this.helpProvider1.HelpNamespace = "mspaint.chm";

        // Sets properties for the different address fields.

        // Address TextBox
        this.addressTextBox.Location = new System.Drawing.Point(16, 24);
        this.addressTextBox.Size = new System.Drawing.Size(264, 20);
        this.addressTextBox.TabIndex = 0;
        this.addressTextBox.Text = "";

        // City TextBox
        this.cityTextBox.Location = new System.Drawing.Point(16, 48);
        this.cityTextBox.Size = new System.Drawing.Size(120, 20);
        this.cityTextBox.TabIndex = 3;
        this.cityTextBox.Text = "";

        // State TextBox
        this.stateTextBox.Location = new System.Drawing.Point(152, 48);
        this.stateTextBox.MaxLength = 2;
        this.stateTextBox.Size = new System.Drawing.Size(32, 20);
        this.stateTextBox.TabIndex = 5;
        this.stateTextBox.Text = "";

        // Zip TextBox
        this.zipTextBox.Location = new System.Drawing.Point(192, 48);
        this.zipTextBox.Size = new System.Drawing.Size(88, 20);
        this.zipTextBox.TabIndex = 6;
        this.zipTextBox.Text = "";

        // Add the controls to the form.
        this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                    this.zipTextBox, this.stateTextBox,
                                    this.label3, this.cityTextBox,
                                    this.label2, this.helpLabel,
                                    this.addressTextBox});

        // Set the form to look like a dialog, and show the HelpButton.    
        this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
        this.HelpButton = true;
        this.MaximizeBox = false;
        this.MinimizeBox = false;
        this.ClientSize = new System.Drawing.Size(292, 160);
        this.Text = "Help Provider Demonstration";
    }
}

Remarks

If you previously called the SetHelpString or SetHelpKeyword for the control specified in the ctl parameter, the HelpProvider automatically displays Help for that control. To modify this behavior, call the SetShowHelp method, specifying false in the value parameter.

Applies to

Продукт Версії
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
Windows Desktop 3.0, 3.1, 5, 6, 7, 8, 9

See also