Herfried K. Wagner [MVP] wrote:
"juky" <ju*******@yahoo.com> schrieb: I have 2 applications one in VB.net and the other in VC6. I need to
pass data between them. How can I do it? what's the best way to
implement such communication ?
You can set up communication using 'WM_COPYDATA', for example:
<URL:http://groups.google.de/groups?selm=uWYQZLWjDHA.3312%40tk2msftngp13.phx.gb l>
--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>
I just checked your link about WM_COPYDATA, it's pretty useful. I
copied below the example.The problem is to synchronize sender and
receiver with Sender and receiver on the other application written in
VC6. How should Sender and receiver look like in VC if I want to use
this vb.net example in application-1?
Thanks,
Juky
Application 1 - the receiver...
Imports System.Runtime.InteropServices
Public Class MainForm
Inherits System.Windows.Forms.Form
#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)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer
'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.
Friend WithEvents Messages As System.Windows.Forms.ListBox
<System.Diagnostics.DebuggerStepThrough()> Private Sub
InitializeComponent()
Me.Messages = New System.Windows.Forms.ListBox()
Me.SuspendLayout()
'
'Messages
'
Me.Messages.Dock = System.Windows.Forms.DockStyle.Fill
Me.Messages.IntegralHeight = False
Me.Messages.Name = "Messages"
Me.Messages.Size = New System.Drawing.Size(292, 273)
Me.Messages.TabIndex = 0
'
'MainForm
'
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(292, 273)
Me.Controls.AddRange(New System.Windows.Forms.Control()
{Me.Messages})
Me.Name = "MainForm"
Me.Text = "Receive WM_COPYDATA"
Me.ResumeLayout(False)
End Sub
#End Region
Protected Overrides Sub WndProc(ByRef m As
System.Windows.Forms.Message)
If m.Msg = MainForm.WM_COPYDATA Then
Dim data As CopyData
Dim message As String
' get the data...
data = CType(m.GetLParam(GetType(CopyData)), CopyData)
message = Marshal.PtrToStringAuto(data.lpData, data.cbData
\
Marshal.SystemDefaultCharSize)
' add the message
Messages.Items.Add(String.Format("{0}: {1}",
DateTime.Now.ToShortTimeString(), message))
' let them know we processed the message...
m.Result = New IntPtr(1)
Else
MyBase.WndProc(m)
End If
End Sub
Private Const WM_COPYDATA As Integer = &H4A
<StructLayout(LayoutKind.Sequential)> _
Private Structure CopyData
Public dwData As IntPtr
Public cbData As Integer
Public lpData As IntPtr
End Structure
End Class
Application 2 - The sender....
Imports System.Runtime.InteropServices
Public Class MainForm
Inherits System.Windows.Forms.Form
#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)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer
'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.
Friend WithEvents MessageText As System.Windows.Forms.TextBox
Friend WithEvents Send As System.Windows.Forms.Button
<System.Diagnostics.DebuggerStepThrough()> Private Sub
InitializeComponent()
Me.MessageText = New System.Windows.Forms.TextBox()
Me.Send = New System.Windows.Forms.Button()
Me.SuspendLayout()
'
'MessageText
'
Me.MessageText.Anchor = ((System.Windows.Forms.AnchorStyles.Top
Or
System.Windows.Forms.AnchorStyles.Left) _
Or System.Windows.Forms.AnchorStyles.Right)
Me.MessageText.Name = "MessageText"
Me.MessageText.Size = New System.Drawing.Size(328, 20)
Me.MessageText.TabIndex = 0
Me.MessageText.Text = ""
'
'Send
'
Me.Send.Anchor = System.Windows.Forms.AnchorStyles.Top
Me.Send.Location = New System.Drawing.Point(127, 32)
Me.Send.Name = "Send"
Me.Send.TabIndex = 1
Me.Send.Text = "Send"
'
'MainForm
'
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(328, 61)
Me.Controls.AddRange(New System.Windows.Forms.Control()
{Me.Send,
Me.MessageText})
Me.Name = "MainForm"
Me.Text = "Send Data To Client Using WM_COPYDATA"
Me.ResumeLayout(False)
End Sub
#End Region
Private Const WM_COPYDATA As Integer = &H4A
Private Const WindowName As String = "Receive WM_COPYDATA"
<StructLayout(LayoutKind.Sequential)> _
Private Structure CopyData
Public dwData As IntPtr
Public cbData As Integer
Public lpData As IntPtr
End Structure
Private Declare Auto Function SendMessage Lib "user32" _
(ByVal hWnd As IntPtr, _
ByVal Msg As Integer, _
ByVal wParam As IntPtr, _
ByRef lParam As CopyData) As Boolean
Private Declare Auto Function FindWindow Lib "user32" _
(ByVal lpClassName As String, _
ByVal lpWindowName As String) As IntPtr
Private Sub Send_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Send.Click
Dim ClientWindow As IntPtr = MainForm.FindWindow(Nothing,
MainForm.WindowName)
' make sure we found an active client window
If Not ClientWindow.Equals(IntPtr.Zero) Then
' if there is text to send
If Me.MessageText.Text.Length > 0 Then
Dim message As String = Me.MessageText.Text
Dim data As CopyData
' set up the data...
data.lpData = Marshal.StringToHGlobalAuto(message)
data.cbData = message.Length *
Marshal.SystemDefaultCharSize
' send the data
MainForm.SendMessage(ClientWindow,
MainForm.WM_COPYDATA,
Me.Handle, data)
' free the pointer...
Marshal.FreeHGlobal(data.lpData)
End If
Else
MessageBox.Show("Could Not Find Active Client Window.")
End If
End Sub
End Class
