In this example we will use the Compact
Framework to create a program containing a launch pad for the Pocket PC. Our
program will provide an integrated interface to launch some of the common
programs on the Pocket PC. This sample serves to demonstrate the use of the
Pinvoke mechanism on the Pocket PC to launch external programs such as Internet
Explorer and Calculator. This example can be extended to create a convenient
toolbox for launching frequently used Pocket PC programs.
The Compact Framework does not have complete support for COM Interop and
interoperating with ActiveX controls. It provides the Platform Invoke mechanism
for calling unmanaged DLLs. We will explore this functionality more in detail in
this example.
The complete code listing along with sample screenshots follow.
The core of our example consists of using C# 's DLLImport attribute to access
the "CreateProcess" function from the unmanaged DLL coredll.dll. This function
is invoked in the program to launch the program as specified in the parameters.
![sde_launch_1-in-vb.net.jpg]()
Figure: Launchpad Application in Action
![Internationaliziing1-in-vb.net.gif]()
Figure: PocketPc.com site opened from the LaunchPad program through a single
button click
Complete Code Listing
Imports
System
Imports
System.Drawing
Imports
System.Collections
Imports
System.Windows.Forms
Imports
System.Data
Imports
System.Runtime.InteropServices
Public
Class Form1
Inherits
System.Windows.Forms.Form
Private
button1 As System.Windows.Forms.Button
Private
button3 As System.Windows.Forms.Button
Private
button2 As System.Windows.Forms.Button
Private
button4 As System.Windows.Forms.Button
Private
button5 As System.Windows.Forms.Button
Private
mainMenu1 As System.Windows.Forms.MainMenu
#Region " Windows Form Designer generated
code "
Public
Sub New()
MyBase.New()
'This call is required by
the Windows Form Designer.
InitializeComponent()
'Add any initialization
after the InitializeComponent() call
End
Sub
'Form overrides
dispose to clean up the component list.
Protected
Overloads
Overrides Sub Dispose(ByVal
disposing As
Boolean)
MyBase.Dispose(disposing)
End
Sub
'NOTE: The
following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
Private
Sub InitializeComponent()
Me.mainMenu1
= New System.Windows.Forms.MainMenu
Me.button1
= New System.Windows.Forms.Button
Me.button3
= New System.Windows.Forms.Button
Me.button2
= New System.Windows.Forms.Button
Me.button4
= New System.Windows.Forms.Button
Me.button5
= New System.Windows.Forms.Button
'button1
Me.button1.Location
= New System.Drawing.Point(40, 16)
Me.button1.Size
= New System.Drawing.Size(96, 32)
Me.button1.Text
= "PocketPc.Com"
AddHandler
button1.Click, AddressOf button1_Click
'button3
Me.button3.Location
= New System.Drawing.Point(40, 64)
Me.button3.Size
= New System.Drawing.Size(96, 32)
Me.button3.Text
= "IE"
AddHandler
button3.Click, AddressOf button3_Click
'button2
Me.button2.Location
= New System.Drawing.Point(40, 112)
Me.button2.Size
= New System.Drawing.Size(96, 32)
Me.button2.Text
= "Calculator"
AddHandler
button2.Click, AddressOf button2_Click
'button4
Me.button4.Location
= New System.Drawing.Point(40, 160)
Me.button4.Size
= New System.Drawing.Size(96, 32)
Me.button4.Text
= "Calendar"
AddHandler
button4.Click, AddressOf button4_Click
'button5
Me.button5.Location
= New System.Drawing.Point(40, 208)
Me.button5.Size
= New System.Drawing.Size(96, 32)
Me.button5.Text
= "Tasks"
AddHandler
button5.Click, AddressOf button5_Click
'Form1
Me.Controls.Add(Me.button5)
Me.Controls.Add(Me.button4)
Me.Controls.Add(Me.button2)
Me.Controls.Add(Me.button3)
Me.Controls.Add(Me.button1)
Me.Menu
= Me.mainMenu1
Me.Text
= "Form1"
End
Sub
Shared Sub
Main()
Application.Run(New Form1)
End
Sub
'Main
#End
Region
Private Sub
button1_Click(ByVal sender
As System.Object,
ByVal e As
System.EventArgs)
ShowPPCWebSite()
End
Sub
Private Sub
button2_Click(ByVal sender
As System.Object,
ByVal e As
System.EventArgs)
StartCalc()
End
Sub
Private Sub
button3_Click(ByVal sender
As System.Object,
ByVal e As
System.EventArgs)
StartIE()
End
Sub
Private Sub
button4_Click(ByVal sender
As System.Object,
ByVal e As
System.EventArgs)
StartCalendar()
End
Sub
Private Sub
button5_Click(ByVal sender
As System.Object,
ByVal e As
System.EventArgs)
StartTasks()
End
Sub
Private Declare
Function CreateProcess
Lib "coredll.Dll" (ByVal
strImageName As
String,
ByVal strCmdLine As
String,
ByVal pProcessAttributes As IntPtr,
ByVal pThreadAttributes
As IntPtr,
ByVal bInheritsHandle As
Integer,
ByVal dwCreationFlags As
Integer,
ByVal pEnvironment As IntPtr,
ByVal pCurrentDir
As IntPtr,
ByVal bArray() As [Byte],
ByVal oProc
As ProcessInfo) As
Integer
Private Sub
ShowPPCWebSite()
Dim
pi As New
ProcessInfo
CreateProcess("iexplore.exe", "www.microsoft.com/mobile/pocketpc/default.asp",
IntPtr.Zero, IntPtr.Zero, 0, 0, IntPtr.Zero, IntPtr.Zero,
New [Byte](128) {}, pi)
End
Sub
'ShowPPCWebSite
Private
Sub StartIE()
Dim
pi As New
ProcessInfo
CreateProcess("iexplore.exe", "", IntPtr.Zero, IntPtr.Zero, 0, 0, IntPtr.Zero,
IntPtr.Zero, New [Byte](128) {}, pi)
End
Sub
'StartIE
Private
Sub StartCalc()
Dim
pi As New
ProcessInfo
CreateProcess("calc.exe", "", IntPtr.Zero, IntPtr.Zero, 0, 0, IntPtr.Zero,
IntPtr.Zero, New [Byte](128) {}, pi)
End
Sub
'StartCalc
Private
Sub StartCalendar()
Dim
pi As New
ProcessInfo
CreateProcess("calendar.exe", "", IntPtr.Zero, IntPtr.Zero, 0, 0, IntPtr.Zero,
IntPtr.Zero, New [Byte](128) {}, pi)
End
Sub
'StartCalendar
Private
Sub StartTasks()
Dim
pi As New
ProcessInfo
CreateProcess("tasks.exe", "", IntPtr.Zero, IntPtr.Zero, 0, 0, IntPtr.Zero,
IntPtr.Zero, New [Byte](128) {}, pi)
End
Sub 'StartTasks
End
Class
Public Class
ProcessInfo
Public
Process As
Integer
Public Thread As
Integer
Public ProcessID As
Integer
Public ThreadID As
Integer
End Class
'ProcessInfo
NOTE:
This article is purely for demonstration. This article should not be construed
as a best practices white paper. This article is entirely original, unless
specified. Any resemblance to other material is an un-intentional coincidence
and should not be misconstrued as malicious, slanderous, or any anything else
hereof.
Conclusion:
In this article, we explored the code to launch external applications on Pocket
PC using Pinvoke and unmanaged DLLs. I would like to give credit to Scott
Swigart for his valuable inputs on support newsgroups.v