Envoyer un message à un processus Windows (pas sa fenêtre principale)

Les tuyaux nommés peuvent être utilisés pour cela. C'est peut-être la méthode plus acceptable avec .NET.Vous pouvez définir un service dans l'application principale qui accepte un message à partir de l'application d'appel. Voici un échantillon du service, en VB. Il appelle l'application principale et transmet une chaîne à ce cas, dans ce cas, un nom de fichier. Il renvoie également une chaîne, mais tous les paramètres peuvent être utilisés ici.

Imports System.Diagnostics
Imports System.ServiceModel
Imports System.IO
Imports vb = Microsoft.VisualBasic

Module MainAppLoader

Sub Main()

Dim epAddress As EndpointAddress
Dim Client As picClient
Dim s As String
Dim loadFile As String
Dim procs() As Process
Dim processName As String = "MainApp"

loadFile = "" ' filename to load

procs = Process.GetProcessesByName(processName)

If UBound(procs) >= 0 Then
  epAddress = New EndpointAddress("net.pipe://localhost/MainAppPicLoad")
  Client = New picClient(New NetNamedPipeBinding, epAddress)
  s = Client.LoadPic(loadFile)
End If

End Sub

<System.Diagnostics.DebuggerStepThroughAttribute(), _
 System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "3.0.0.0")> _
Partial Public Class picClient
    Inherits System.ServiceModel.ClientBase(Of IMainAppPicLoad)
    Implements IMainAppPicLoad

    Public Sub New(ByVal binding As System.ServiceModel.Channels.Binding, ByVal remoteAddress As System.ServiceModel.EndpointAddress)
        MyBase.New(binding, remoteAddress)
    End Sub

    Public Function LoadPic(ByVal fName As String) As String Implements IMainAppPicLoad.LoadPic
        Return MyBase.Channel.LoadPic(fName)
    End Function

End Class

' from here down was auto generated by svcutil.
' svcutil.exe /language:vb /out:generatedProxy.vb /config:app.config http://localhost:8000/MainAppPicLoad
' Some has been simplified after auto code generation.
<System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "3.0.0.0"), _
 System.ServiceModel.ServiceContractAttribute(ConfigurationName:="IMainAppPicLoad")> _
Public Interface IMainAppPicLoad
  <System.ServiceModel.OperationContractAttribute(Action:="http://tempuri.org/IMainAppPicLoad/LoadPic", ReplyAction:="http://tempuri.org/IMainAppPicLoad/LoadPicResponse")> _
  Function LoadPic(ByVal fName As String) As String
End Interface

<System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "3.0.0.0")> _
Public Interface IMainAppPicLoadChannel
  Inherits IMainAppPicLoad, System.ServiceModel.IClientChannel
End Interface

<System.Diagnostics.DebuggerStepThroughAttribute(), _
System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "3.0.0.0")> _
Partial Public Class IMainAppPicLoadClient
  Inherits System.ServiceModel.ClientBase(Of IMainAppPicLoad)
  Implements IMainAppPicLoad

  Public Sub New(ByVal binding As System.ServiceModel.Channels.Binding, ByVal remoteAddress As System.ServiceModel.EndpointAddress)
    MyBase.New(binding, remoteAddress)
  End Sub

  Public Function LoadPic(ByVal fName As String) As String Implements IMainAppPicLoad.LoadPic
    Return MyBase.Channel.LoadPic(fName)
  End Function
End Class

End Module

<ServiceContract()> Public Interface IMainAppPicLoad
<OperationContract()> Function LoadPic(ByVal fName As String) As String
End Interface

Pour d'autres personnes souhaitant y parvenir, je pose ci-dessous mon implémentation, à l'aide de la solution de Matt Davis.

dans Program.cs P>

protected override void WndProc(ref Message m)
{
    base.WndProc(ref m);
            //someone (another process) said that we should show the window (WM_ACTIVATEAPP)
    if (m.Msg == Program.WM_ACTIVATEAPP)
        this.Show();
}