Visual Basic .NET Topics: Application Online Help

	Application Online Help

Providing Help

Introduction

Providing help is one of the most neglected areas of development, especially for beginning programmers. There are various reasons to this. Some programmers tend to think that help is such a small job that it should be left to non-programmers. This has never been a valid argument since the person who creates an application knows it more than anybody. This means that asking someone else to create help for an application would only slow the process because the other person would need to have new and more information about the application. Another reason is that, most programmers who want to take care of programming when creating an application think that they are working double to create a single program. This drives them to set this aspect aside and continue only with the application, thinking that they can come back to taking care of help when the application is complete. What makes this unrealistic is that, sometimes when they finish the application, they are "tired".

There are various small techniques you can use to provide help in your application.

Practical Learning: Introducing Help

Start a Windows Application named CIC1
Change the form's Text to Clarksville Ice Cream

Design the form as follows:

Control	Name	Text	Additional Properties
GroupBox
Label		Order Date:
DateTimePicker	dtpOrderDate		Format: Short
Label		Order Time:
DateTimePicker	dtpOrderTime		Format: Time ShowUpDown: True
Label		Flavor:
ComboBox	cboFlavors		DropDownStyle: DropDownList
Label		Container:
ComboBox	cboContainers		DropDownStyle: DropDownList
Label		Ingredient:
ComboBox	cboIngedients		DropDownStyle: DropDownList
Label		Scoops:
TextBox	txtScoops	1	TextAlign: Right
Label		Order Total:
TextBox	txtOrderTotal	0.00	TextAlign: Right
Button	btnCalcTotal	Calculate Total
Button	btnNewOrder	New Order

Click the combo box to the right of the Flavor label. Then, in the Properties, click the ellipsis button

of Items property and create the list with:

Vanilla
Cream of Cocoa
Chocolate Chip
Cherry Coke
Butter Pecan
Chocolate Cookie
Chunky Butter
Organic Strawberry
Chocolate Brownies
Caramel Au Lait

Click OK
Click the combo box to the right of the Container label. Then, in the Properties, click the ellipsis button of Items property and create the list with:

Cone
Cup
Bowl
Click OK
Click the combo box to the right of the Ingredient label. Then, in the Properties, click the ellipsis button of Items property and create the list with:

None
Peanuts
Mixed Nuts
M & M
Cookies
Click OK
Double-click the Calculate Total button to access its Click event

Implement it as follows:

Private Sub btnCalcTotal_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
		Handles btnCalcTotal.Click
        Dim Container As String
        Dim dblPriceByContainer As Double
        Dim Ingredient As Integer
        Dim dblIngredient As Double
        Dim Scoops As Integer
        Dim dblScoops As Double
        Dim OrderTotal As Double

        ' First find out what container the customer requested
        Container = Me.cboContainers.Text

        ' The price of a container depends on which one the customer selected
        If Container = "Cone" Then
            dblPriceByContainer = 0.55
        ElseIf Container = "Cup" Then
            dblPriceByContainer = 0.75
        Else
            dblPriceByContainer = 1.15
        End If

        ' Find out if the customer wants any ingredient at all
        Ingredient = Me.cboIngredient.SelectedIndex

        ' If the customer selected an ingredient, which is not "None", add $.95
        If Ingredient > 1 Then
            dblIngredient = 0.95
        End If

        ' Get the number of scoops
        Scoops = CInt(Me.txtScoops.Text)
        If Scoops = 2 Then
            dblScoops = 2.55
        ElseIf Scoops = 3 Then
            dblScoops = 3.25
        Else
            dblScoops = 1.85
        End If

        ' Make sure the user selected a flavor, otherwise, there is no reason to process an order
        If Me.cboFlavors.SelectedIndex > 0 Then
            OrderTotal = dblScoops + dblPriceByContainer + dblIngredient
            Me.txtOrderTotal.Text = OrderTotal.ToString("C")
        End If
    End Sub

Double-click the New Order button to access its Click event and implement it as follows:

Private Sub btnNewOrder_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
		Handles btnNewOrder.Click
        ' If the user clicks New Order, we reset the form with the default values
        Me.dtpOrderDate.Value = DateTime.Today
        Me.dtpOrderTime.Value = DateTime.Now
        Me.cboFlavors.SelectedIndex = -1
        Me.cboContainers.SelectedIndex = -1
        Me.cboIngredient.SelectedIndex = 0
        Me.txtScoops.Text = "1"
        Me.txtOrderTotal.Text = "0.00"
End Sub

Test the application. Here is an example:
Close the form and return to Visual Studio

Status Bar Messages

One way you can provide simple help consists of displaying short indicative messages on a status bar. To do this, you can first create sections, called panels, on a status bar and then display the necessary messages in the section of your choice. The message can be anything but it should consist of just a few words to fit in its section without going over board.

Practical Learning: Helping Through a Status Bar

Display the from and expand its bottom border a little bit
On the Toolbox, click StatusBar and click the bottom section of the form
In the Properties window, set the ShowPanels property to True
To create the sections of the status bar, click the ellipsis button of the Panels field
In the StatusBarPanel Collection Editor, click Add and change the following values:
Width: 340
Text: Ready
Click Add and change the following value:
Width: 60
Text: Delete the text
Click OK
Right-click anywhere in the form and click View Code
In the Class Name combo box, select dtpOrderDate. In the Method Name, click GotFocus
In the same way, initiate the GotFocus event of the dtpOrderTime date time picker, the cboFlavors combo box, the cboContainers combo box, the cboIngredients combo box, the txtScoops text box, and the txtOrderTotal text box

Implement the events as follows:

    ' Display a friendly message in the left section of the status bar
    Private Sub dtpOrderDate_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles dtpOrderDate.GotFocus
        Me.StatusBar1.Panels(0).Text = "Specify the date this order was processed"
    End Sub

    Private Sub dtpOrderTime_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles dtpOrderTime.GotFocus
        Me.StatusBar1.Panels(0).Text = "Specify the time this order was processed"
    End Sub
    
    Private Sub cboFlavors_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles cboFlavors.GotFocus
        Me.StatusBar1.Panels(0).Text = "Select the customer's desired flavor"
    End Sub

    Private Sub cboContainers_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles cboContainers.GotFocus
        Me.StatusBar1.Panels(0).Text = "Select the type of object that will contain the ice cream"
    End Sub

    Private Sub cboIngredient_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles cboIngredient.GotFocus
        Me.StatusBar1.Panels(0).Text = "Select an ingredient to ""spice"" the ice cream"
    End Sub

    Private Sub txtScoops_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles txtScoops.GotFocus
        Me.StatusBar1.Panels(0).Text = "Select the number of scoops to fill the container"
    End Sub

    Private Sub txtOrderTotal_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles txtOrderTotal.GotFocus
        Me.StatusBar1.Panels(0).Text = "This displays the total of the order"
    End Sub

Test the application
After using it, close the form and return to Visual Studio

Tool Tips

A tool tip is a small yellow box that displays a word or a group of words when the user positions the mouse on top of a control:

To create a tool tip system in a Visual Studio application, first add a ToolTip control to a form. After adding a ToolTip control, the form and all controls on it receive a new field in the Properties window. If the new ToolTip control is called ToolTip1, the new field in the Properties window for each control is ToolTip on ToolTip1. To display a tool tip for a control, first click it on the form. Then, in the Properties window, click ToolTip on ToolTip1, and type the desired tool tip.

Practical Learning: Adding Tool Tips

To prepare for tool tips, on the Toolbox, click ToolTip and click the form

On the form, click each control and, in the Properties window, set its ToolTip On ToolTip1 property as follows:

Control	ToolTip On ToolTip1
dtpOrderDate	Click the arrow to select a date
dtpOrderTime	Click each section, then click one of the arrows to change its value
cboFlavors	Click the arrow to display a list, then select a flavor from the list
cboContainers	Click to display the list of containers and select one
cboIngedients	Display the list of ingredients and make the customer's choice
txtScoops	Enter the number of scoops (1, 2, or 3) to fill the container
txtOrderTotal	This displays the total amount of this order
btnCalcTotal	Click here to calculate the total of the order
btnNewOrder	Click here to reset the form

Test the application
Close it and return to Visual Studio

Online Help

Introduction

Online help is the system of providing help files with an application. Online help is usually available from the main menu through a menu group created under a Help category.

In the past, the techniques to provide or program online help were not always easy. The early implementations of help were created in a system called WinHelp. This required using a Rich Text Format (rtf) file and appropriately formatting it. It is possible that, when folks at Microsoft developed WinHelp, they had only Microsoft Word in mind. It was difficult to get the required file ready if you were using another application such as WordPad or WordPerfect... Creating the help file was not enough. Once the file was ready, it had to be added to the application, and appropriately. This back and forth gymnastic was a great motivation for neglect. As if these difficulties were not enough, or because of these difficulties, Microsoft created another system called HTML Help. This neither solved most problems nor created an easier solution. At this time, this HTML Help is widely used and many companies, such as AutoDesk (AutoCAD) and Macromedia to name just two, have adopted it . Many companies such as Borland, Jasc, just to name two, are still using WinHelp. This indicates that HTML Help didn't solve all problems and was not anonymously adopted.

Because HTML Help is the most supported help system by Microsoft, we will use it. Also, it is easier to use HTML Help in a Microsoft Visual Studio application than to use WinHelp.

Practical Learning: Introducing Online Help

To create a new form, on the main menu, click Project -> Add Windows Form...
In the Add New Item dialog box, change the name of the form to Calculation and press Enter

Design the new form as follows:

Clarksville Ice Scream - Difference Calculation

Control	Name	Text	Additional Properties
Label		Order Total:
TextBox	txtOrderTotal	0.00	TextAlign: Right
Label		Amount Tended:
TextBox	txtAmountTended	0.00	TextAlign: Right
Button	btnCalculate	Calculate
Label		Difference:
TextBox	txtDifference	0.00	TextAlign: Right
Button	btnClose	Close

Double-click both buttons and implement their Click events as follows:

Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
        Dim TotalOrder As Double
        Dim AmountTended As Double
        Dim Difference As Double

        ' Get the value of the total order. Actually, this value will be provided by the main form
        TotalOrder = CDbl(Me.txtTotalOrder.Text)
        ' The amount tended will be entered by the user
        AmountTended = CDbl(Me.txtAmountTended.Text)
        ' Calculate the difference of both values, assuming that the amount tended is higher
        Difference = AmountTended - TotalOrder

        ' Display the result in the Difference text box
        Me.txtDifference.Text = Difference.ToString("C")
End Sub

Private Sub btnClose_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClose.Click
        Close()
End Sub

Display the first form (Form1.vb [Design])
Add a new button to the bottom-right side of the form
Change its values in the Properties window as follows:
Name: btnCalcDifference
Text: Calculate Difference
Enabled: False
ToolTip on ToolTip1: Click to calculate the amount owed to the customer

Double-click the Calculate Difference button and implement its Click event as follows:

Private Sub btnCalcDifference_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalcDifference.Click
        ' Declare a variable for the Calculation form
        Dim dlgCalculation As New Calculation

        ' Transfer the current value of the Order Total text box from the main form to the other form
        dlgCalculation.txtTotalOrder.Text = Me.txtOrderTotal.Text
        ' Display the other form
        dlgCalculation.ShowDialog()
End Sub

Change the Click events of the Calculate Total and the New Order buttons as follows:

Private Sub btnCalcTotal_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalcTotal.Click
        
        . . . No Change

        ' Make sure the user selected a flavor, otherwise, there is no reason to process an order
        If Me.cboFlavors.SelectedIndex > 0 Then
            OrderTotal = 2.25 + dblPriceByContainer + dblIngredient
            Me.txtOrderTotal.Text = OrderTotal.ToString("C")
            ' Once an order has been processed, the user should be able to calculate the difference
            Me.btnCalcDifference.Enabled = True
        End If
End Sub

Private Sub btnNewOrder_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNewOrder.Click
        ' If the user clicks New Order, we reset the form with the default values
        Me.dtpOrderDate.Value = DateTime.Today
        Me.dtpOrderTime.Value = DateTime.Now
        Me.cboFlavors.SelectedIndex = -1
        Me.cboContainers.SelectedIndex = -1
        Me.cboIngredient.SelectedIndex = 0
        Me.txtScoops.Text = "1"
        Me.txtOrderTotal.Text = "0.00"
        ' When the customer form is reset, the Calculate Difference button should be disabled
        Me.btnCalcDifference.Enabled = False
End Sub

Test the application. Here is an example:
After using it, close it and return to Visual Studio

The Help Provider

Context-sensitive help allows the user to get local help on a particular control. This works by the user who can first click a control and then press Shift+F1. This displays a yellow box with a word or a group of words:

This help is easier to provide in a dialog box because a dialog has a feature not available on a form. It consists of adding a button with a question mark and then creating the words that would display eventually. When you create this type of dialog box, the user can click the question marked button and click a control. The user can also press Shift+F1. This causes the mouse pointer to be equipped with a question mark. The user can then click a control and a yellow box would appear for that control, providing help.

To make it easy to provide online help in a Visual Studio application, the .NET Framework provides the HelpProvider control. After adding this control to the application, the form and all controls on it receive a new property labeled HelpString On HelpProvider1. You can then type the desired string in the field of the Properties window for each control that would display context-sensitive help.

Practical Learning: Using Context-Sensitive Help

Display the Calculation form and click an area area to select the form
Change the following values of the form in the Properties window (all of these properties will be explained in a future lesson on forms):
FormBorderStyle: Fixed Dialog
HelpButton: True
MaximizeBox: False
MinimizeBox: False
ShowInTaskbar: False
On the Toolbox, click HelpProvider and click the form

Using the Properties window, change the following values for the indicated controls:

Control	HelpString On HelpProvider1
txtOrderTotal	This is the total amount of the current order
txtAmountTended	This is the amount the customer tended
btnCalculate	Click here to calculate the difference between the amount tended and the total price of the order
txtDifference	This displays the difference between the amount tended and the total of the order
btnClose	Click here to close the dialog box

Execute the application
When it displays, process an order and click the Calculate Difference button
In the Calculation dialog box, click the question mark button in the title bar and click on the text boxes or buttons
After using the application, close the forms and return to Visual Studio
Display the main form (Form1.vb [Design])
To add a menu to the application, on the Toolbox, click MainMenu and click the form
On the form, click Type Here. Type &File and press the down arrow key
Type E&xit and press Enter
On the right side of File (on the form), click Type Here
Type &Help and press the down arrow key
Type &Contents... and press the down arrow key
Type &Index... and press the down arrow key
Type &Search... and press Enter
On the form, click File and double-click Exit

Implement its event as follows:

Private Sub MenuItem2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MenuItem2.Click
        End
End Sub

Test the application then close it and return to Visual Studio

Introduction to HTML Help

The online help we described above provides only small yellow boxes. It is called context-sensitive because it provides its assistance on only a control of the form. Another technique, in fact highly supported with any commercial program, consists of providing an external application that resembles a book. This allows the user to get more detailed information about almost any aspect of the application. To provide online help in a Visual Studio application, you can use an external system. This consists of creating a complete application whose only purpose is to describe another application. This means that, in the beginning, both applications are not related in any way. With HTML Help, you must first create HTML files. You create these files anyway you like but, in this case, they are meant to provide support for a specific application. Therefore, when creating the files, try to divide them by issues. For example, you can create a file for each form of your application and use that file to describe what the form or dialog box is used for. You still can use any approach to create the files you would need. Experience will guide you eventually into knowing what to put in those files.

After creating the HTML files, you can open HTML Help Workshop which is a complete but separate application. This application is freely available from Microsoft and you can download it from the MSDN web site.

Practical Learning: Creating an HTML Help File

Using Windows Explorer or My Computer, create a folder named cis
Inside of the cis folder, create a folder named images
Save the following pictures in the cis\images folder:

Start Notepad and create a Cascading Style Sheet file to format the body tag and the main title of the pages. Here is an example:

body
{
	font-size: 10pt;
	color: black;
	margin-top: 0pt;
	margin-left: 0pt;
	font-family: Verdana, Tahoma, Arial, Sans-Serif;
}

.maintitle
{
	font-weight: bold;
	font-size: 24pt;
	color: blue;
	font-family: Garamond, Georgia, 'Times New Roman' , Serif;
}

Save the file as cis.css in the cis folder

Start another file with the following contents

<html>

<head>

<link rel="stylesheet" type="text/css" href="cis.css">

<title>Overview of Clarksville Ice Cream</title>
</head>

<body>

<table border="0" width="100%" cellspacing="0" cellpadding="0">
  <tr>
    <td width="100%" align="center"><p class="maintitle">Overview of Clarksville Ice Cream</p></td>
  </tr>
  <tr>
    <td width="100%" bgcolor="#0000FF" height="2"></td>
  </tr>
</table>

<p>&nbsp;</p>
<center><img border="0" src="images/main1.gif" alt="The main window of the application" width="424" height="295"></center>
<p>Clarksville Ice Cream is a computer application used to process customers
orders. It allows an employee to receive requests from a customer, based on what
is available in the menu. When the order is complete, an ice cream is
&quot;prepared&quot; and handed to the customer. As a commercial business, the
application calculates the total amount. The amount is read to the customer who
hands money to the clerk to complete the transaction</p>

</body>

</html>

Save it as introduction.htm

Start another file with the following contents

<html>

<head>

<link rel="stylesheet" type="text/css" href="cis.css">

<title>Customer Order Form</title>
</head>

<body>

<table border="0" width="100%" cellspacing="0" cellpadding="0">
  <tr>
    <td width="100%" align="center">
      <p class="maintitle">Customer Order Form</p>
    </td>
  </tr>
  <tr>
    <td width="100%" bgcolor="#0000FF" height="2"></td>
  </tr>
</table>

<p>&nbsp;</p>
<p>The main or opening window of this application displays a form used to
process customers orders. The top section of the form, also called the title
bar, is equipped with a menu called the main menu. this menu allows the user to
start a new order or to close the application. To use this main menu, you can
click one of the top-level words such as File. This causes the menu category of
your choice to expand:</p>
<center><img border="0" src="images/main2.gif" alt="The main menu" width="424" height="295"></center>
<p>After using a menu item, you can click it or click somewhere else to collapse
it.</p>

<p>The other objects on the main form allow the user to process an order by
selecting items from the Windows controls. Once an order is ready, the user can
click the Calculate Total button. This evaluates the total price of the order
and displays it in the text box on the right side of Order Total.</p>

<p>To start a new customer order, the user can click the New Order button. This
resets all controls on the form:</p>

<center><img border="0" src="images/main3.gif" alt="Customer Form Reset" width="424" height="295"></center>

<p>When an order has been calculated, the user can click the Calculate
Difference button to evaluate the diffence.</p>

</body>

</html>

Save it as mainform.htm

Start another file with the following contents

<html>

<head>

<link rel="stylesheet" type="text/css" href="cis.css">

<title>Difference Calculation</title>
</head>

<body>

<table border="0" width="100%" cellspacing="0" cellpadding="0">
  <tr>
    <td width="100%" align="center">
      <p class="maintitle">Difference Calculation</p>
    </td>
  </tr>
  <tr>
    <td width="100%" bgcolor="#0000FF" height="2"></td>
  </tr>
</table>

<p>&nbsp;</p>
<p>The Calculation dialog box allows a user to easily calculate the amount of
money owed to a customer. After a customer has placed an order and given money
to the clerk, the user can display this dialog box. When it comes up, the top
text box of this window already displays the amount of the customer's order. The
user can then simply enter the amount the customer gave in the Amount Tended
text box. Then the user can click Calculate</p>
<center><img border="0" src="images/calculation1.gif" width="304" height="152"></center>
<p>When the user has clicked the Calculate button, it calculates the difference
and displays it in the Difference text box. After using this dialog box, the
user can close it by clicking Close.</p>
<p>&nbsp;</p>

</body>

</html>

Save it as calculation.htm

Start another file with the following contents

<html>

<head>

<title>Clarksville Ice Cream - Home</title></head>

<body>
<h1>Clarksville Ice Cream</h1>
<p><a href="introduction.htm">Introduction</a></p>
<p><a href="mainform.htm">The Main Form</a></p>
<p><a href="calculation.htm">The Difference Calculation Dialog Box</a></p>
</body>

</html>

Save it as index.htm
Start HTML Help Workshop
On the main menu of HTML Help Workshop, click File -> New
In the New dialog box, make sure Project is selected and click OK
In the first page of the New Project wizard, click Next
In the second page of the wizard, click Browse
Locate the cis folder you created and display it in the Save In combo box
Set the File Name to cisoh
Click Open
In the second page, click Next
In the third page, read the text. Click the HTML files (.htm) check box and click Next
In the fourth page, click Add
In the Open dialog box, press and hold Ctrl. Then click each htm file to select them all
Click Open
In the fourth page, click Next
In the last page of the wizard, click Finish
In HTML Help Workshop, click the Contents tab
In the dialog box that displays, make sure the first radio button is selected
Click OK
In the Save As dialog box, change the name of the file to CISContents
Click Save
Click the Insert a Heading button
In the Table Of Contents Entry dialog box, in the Entry Title text box, type Clarksville Ice Cream and click Add
In the Path Or URL dialog box, select the Clarksville Ice Cream - Home and click OK
Click OK
Click the Insert A Page button
In the message box that displays, click No
In the Entry Title text box, type Introduction and click Add
In the Path Or URL dialog box, select the Overview of Clarksville Ice Cream and click OK
In the Table Of Contents Entry dialog box, click OK

In the same way, create new pages under the Introduction heading using the following table

New Page Title	Page or URL
Customer Order Form	Customer Order Form
Difference Calculation	Difference Calculation

In HTML Help Workshop, click the Index tab. In the dialog box that comes up, make sure the top radio button is selected
Click OK
Set the name of the file to CISIndex and press Enter
Click Insert A Keyword
In the Keyword text box, type Calculation and click Add
In the Path Or URL dialog box, click Difference Calculation and click OK twice

In the same way, create new keywords using the following table (sometimes you may receive a message box asking whether you want to create the keyword above the other; it doesn't matter, for this exercise, whether you click Yes or No):

New Keyword	Page or URL
amount	Difference Calculation
money	Difference Calculation
customer	Difference Calculation
order	Difference Calculation
clerk	Difference Calculation
window	Difference Calculation
Amount Tended	Difference Calculation
Calculate	Difference Calculation
Close	Difference Calculation
computer	Overview of Clarksville Ice Cream
Application	Overview of Clarksville Ice Cream
employee	Overview of Clarksville Ice Cream
menu	Overview of Clarksville Ice Cream
commercial	Overview of Clarksville Ice Cream
business	Overview of Clarksville Ice Cream
transaction	Overview of Clarksville Ice Cream
Main Menu	Customer Order Form
category	Customer Order Form
choice	Customer Order Form

Click the Sort Keywords Alphabetically button
Click the Project tab
Click the Add/Modify Window Definitions button
Set the name to MainWnd and press Enter
Set the Title Bar Text to Clarksville Ice Cream
Click the Buttons tab then click the Home and the Locate check boxes
Click the Position tab
Set the Width to 800 and the Height to 600
Click the Files tab
Set the Default and the Home choices to index.htm
Click the Navigation Pane tab
Click the Search Tab check box
Click OK
When the Resolve Window Definition wizard comes up, in the first page, make sure the window defined previously is selected in the Window Type combo box. Click the Compile Full-Text Information check box
Click Next
In the second page, accept the defaults and click Next
In the third page, accept the default and click Finish
To create the help file, click the Save All Files And Compile button

HTML Help and Visual Studio Applications

After creating the HTML Help application, you can use a HelpProvider control to connect it to your application. The HelpProvider control is equipped wit the HelpNamespace provider. This property allows you to specify the application that contains the help application. Besides the HelpNamespace property, the HelpProvider control provides various methods to manage help.

HTML Help can be provided to a Visual Studio application through the Help class defined as follows:

Public Class Help
    Overloads Public Shared Sub ShowHelp(ByVal parent As Control, _
                                                                   ByVal url As String)
    Overloads Public Shared Sub ShowHelp(ByVal parent As Control, _
                                                                   ByVal url As String, _
                                                                   ByVal navigator As HelpNavigator)
    Overloads Public Shared Sub ShowHelp(ByVal parent As Control, _
                                                                   ByVal url As String, _
                                                                   ByVal keyword As String)
    Overloads Public Shared Sub ShowHelp(ByVal parent As Control, _
                                                                   ByVal url As String, _
                                                                   ByVal command As HelpNavigator, _
                                                                   ByVal param As Object)
    Public Shared Sub ShowHelpIndex(ByVal parent As Control, _
                                                           ByVal url As String)
    Public Shared Sub ShowPopup(ByVal parent As Control, _
                                                     ByVal caption As String, _
                                                     ByVal location As Point)
End Class

The overloaded ShowHelp() method is used to specify the help file to display and possibly additional information. Notice that all versions take a first argument as a Control type. This is the parent control from where the online help will be provided.

The first version allows you specify the help file. It can be the help file specified in the HelpProvider.HelpNamespace property mentioned above.

The second and the fourth versions allow you to specify the tab of the HTML Help window to display when the method is called. This is done through the HelpNavigator enumerator that has a value for each tab of the HTML Help window. the fourth version can be used to open the HTML Help window from its Find tab and specify a keyword to search for.

The third version can be used to open a help file based on a keyword.

The ShowHelpIndex() method can be used to open the Index tab of the HTML Help window.

Practical Learning: Providing Online Help to an Application

Open Windows Explorer or My Computer
In the cis folder, copy the cisoh.chm file to the clipboard and paste it in the folder of the current project (CIS1)
Display the main form
On the Toolbox, click HelpProvider and click the form
In the Properties window, change its Name to cisHelp and click HelpNamespace
Click the ellipsis button of the HelpNamespace property
From the CIS1 folder of the current project, select the cisoh.chm file
Click Open
On the main menu of the form, click Help and double-click Contents

Implement the event as follows:

Private Sub MenuItem4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MenuItem4.Click
        Help.ShowHelp(Me, Me.cisHelp.HelpNamespace)
End Sub

Display the main form. On the main menu of the form, double-click Index

Implement the event as follows:

Private Sub MenuItem5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MenuItem5.Click
        Help.ShowHelpIndex(Me, Me.cisHelp.HelpNamespace)
End Sub

Display the main form. On the main menu of the form, double-click Search

Implement the event as follows:

Private Sub MenuItem6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MenuItem6.Click
        Help.ShowHelp(Me, Me.cisHelp.HelpNamespace, HelpNavigator.Find, "")
End Sub

Test the application. When it displays, click the Help menu of the form and click one of the menu items
After using it, close the online help window, close the form, and return to Visual Studio


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