Action

ACTIVEX CONTROLS

629

Action

Result

1

Display a Visual Studio .NET

Command Prompt.

How-to

This is available from the Start

menu in the Microsoft Visual

Studio .NET folder, under the

Visual Studio .NET Tools heading.

2

Create a suitable directory for

holding the generated wrapper

class.

cd Windows Forms\Projects

mkdir WebBrowser

Note: This example uses the

directory “C:\Windows

Forms\Projects\WebBrowser” for

this purpose. You should use an

appropriate directory for your

application.

3

Change the current directory to be

this new directory.

cd WebBrowser

4

Generate the wrapper class by

Two new assemblies are generated in the current

executing the following command:

directory. These are:

aximp

aximp c:\winnt\

c:\winnt\system32\shdocvw.dll

system32\shdocvw.dll

Note: Depending on your operat-

ing system, you may need to

replace “c:\winnt” in this com-

mand with the appropriate Win-

dows directory.

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CHAPTER 18 ODDS AND ENDS .NET

Action

Result

1

In the AboutBox.cs code window,

protected const int SDI_ICON = 0;

create two constants for the two

protected const int MDI_ICON = 1;

types of icons in our image list.

2

Implement an IsMdiApplication

public bool IsMdiApplication

property to define whether the

{

active form is a MDI application.

get { return (lblIcon.ImageIndex

== MDI_ICON); }

How-to

set

a. In the get accessor, return

{

if (value)

whether the current image index

lblIcon.ImageIndex = MDI_ICON;

in the lblIcon control is the

else

MDI icon.

lblIcon.ImageIndex = SDI_ICON;

b. In the set accessor, assign the

}

}

ImageIndex for the lblIcon

control based on the assigned

value setting.

3

Implement an AboutText property

public string AboutText

to get or set the Text property for

{

the lblAboutText control.

get { return lblAboutText.Text; }

set { lblAboutText.Text = value; }

}

4

In the ParentForm class, add a

private void menuAbout_Click

Click handler for the About

(object sender, System.EventArgs e)

MyPhotos menu to create an

{

AboutBox dlg = new AboutBox();

AboutBox instance and assign its

dlg.IsMdiApplication = true;

settings.

Version ver = new

How-to

Version(Application.ProductVersion);

a. Set IsMdiApplication to

dlg.AboutText

true.

= String.Format("MyPhotos (MDI) "

b. Set the AboutText property to

+ "Application, Version {0:#}.{1:#} "

+ "\nSample for /"Windows Forms "

an appropriate string.

+ "Programming with C#\"\nby "

c. Set the Owner property to the

+ "Erik Brown \nCopyright (C) 2001 "

+ "Manning Publications Co.",

current Form.

ver.Major, ver.Minor);

d. Set the dialog’s Icon to use the

dlg.Owner = this;

current form’s icon.

dlg.Icon = this.Icon;

e. Show the dialog.

dlg.Show();

}

ACTIVEX CONTROLS

631

Action

Result

5

Back in the AboutBox class, add a

private void linkClose_LinkClicked

LinkClicked handler for the

(object sender, System.Windows.Forms.

linkClose link label control to

LinkLabelLinkClickedEventArgs e)

{

close the form.

Close();

How-to

}

This is the default event for link

labels, so simply double-click the

link control in the design window.

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CHAPTER 18 ODDS AND ENDS .NET

Action

Result

8

Define the following fields in

private AxWebBrowser browser;

our AboutBox class:

private const string startPage

a. A browser field representing

= "www.manning.com/eebrown";

a WebBrowser control.

Note: The AxWebBrowser class here is based on

b. A constant string contain-

Microsoft’s SHDocVw.dll library from the Windows

ing the web site we will dis-

directory. We will not cover the contents of this

play.

library in detail, as it is beyond the scope of our cur-

rent discussion. Look up the WebBrowser Control

index entry in the online documentation provided

with Visual Studio .NET for more information on this

class.

9

Add a LinkLabel event

private void linkWebSite_LinkClicked

handler for the linkWebSite

(object sender, System.Windows.Forms.

control.

LinkLabelLinkClickedEventArgs e)

{

10

If the browser control already

if (browser != null)

exists, then shut down the

{

web site and hide the Panel

// Shut down existing browser

pnlWebSite.Visible = false;

object.

browser.Dispose();

Note: This code resets the

browser = null;

dialog to its original state.

// Reset dialog settings

linkWebSite.Text

= "Click for book's web site";

this.Size = new Size(400, 140);

this.Text = "About MyPhotos";

}

11

If the browser control does not

else

exist, then create the browser

{

and define some initial

// Create web browser object

browser = new AxWebBrowser();

settings.

browser.Dock = DockStyle.Fill;

How-to

browser.TitleChange += new

a. Create a new AxWeb-

DWebBrowserEvents2_TitleChangeEventHandler

Browser control.

(this.browser_TitleChange);

b. Set its Dock property to

browser.HandleCreated += new

EventHandler(this.browser_HandleCreated);

Fill.

c. Add a TitleChange event

Note: The HandleCreated event is inherited from

handler.

the Control class and uses the familiar mechanism.

d. Add a HandleCreated

The TitleChange event is part of the WebBrowser

event handler.

control, and is part of the AxSHDocVw namespace.

Details on the DWebBrowserEvents2 interface

and the TitleChange event are included with the

online documentation for Visual Studio .NET.

12

Make the Panel control on the

// Show panel containing new browser

form visible and add the

pnlWebSite.SuspendLayout();

browser control to appear

pnlWebSite.Visible = true;

pnlWebSite.Controls.Add(browser);

within this panel.

pnlWebSite.ResumeLayout();

ACTIVEX CONTROLS

633

Action

Result

13

Modify the text displayed for

linkWebSite.Text = "Click to hide web page";

the linkWebSite control and

this.Size = new Size(600, 400);

enlarge the Form to be

}

}

600x400 pixels.

14

Create the handler for the

private void browser_TitleChange

TitleChange event to display

(object sender,

the new document title in the

DWebBrowserEvents2_TitleChangeEvent e)

{

title bar of the AboutBox form.

this.Text = e.text;

}

15

Add a DisplayPage method

protected void DisplayPage(string url)

to navigate to a given URL.

{

How-to

// These are required because the importer

// assumes these are in/out parameters

a. Create object instances to

// and defines them as passed by reference.

represent the reference

object param2 = 0;

object param3 = "";

parameters.

object param4 = "";

b. Display the wait cursor.

object param5 = "";

c. Use the Navigate method

try

to display the given URL.

{

d. Finally, reset the current

Cursor.Current = Cursors.WaitCursor;

browser.Navigate(url,

cursor.

ref param2, ref param3,

Note: The Navigate method

ref param4, ref param5);

is discussed in the online doc-

}

finally

umentation.

{

The four param objects are

Cursor.Current = Cursors.Default;

required here to match the

}

signature of the Navigate

}

method as defined by the

ActiveX Control Importer

(aximp.exe). A future version

of the importer may permit

these settings to be null.

16

Create the handler for the

public void browser_HandleCreated

HandleCreated event to

(object sender, EventArgs evArgs)

display the start page.

{

// The WebBrowser has been created

How-to

// Display the starting page

a. Display the starting page

DisplayPage(startPage);

using the DisplayPage

// Remove this handler

method.

browser.HandleCreated -= new

b. Remove the Handle-

EventHandler(this.browser_HandleCreated);

}

Created handler.

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CHAPTER 18 ODDS AND ENDS .NET