AppDomain.DoCallBack(CrossAppDomainDelegate) Method

Reference

Definition

Namespace:: System

Assembly:: mscorlib.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Executes the code in another application domain that is identified by the specified delegate.

public:
 virtual void DoCallBack(CrossAppDomainDelegate ^ callBackDelegate);

public void DoCallBack (CrossAppDomainDelegate callBackDelegate);

abstract member DoCallBack : CrossAppDomainDelegate -> unit
override this.DoCallBack : CrossAppDomainDelegate -> unit

Public Sub DoCallBack (callBackDelegate As CrossAppDomainDelegate)

Parameters

callBackDelegate: CrossAppDomainDelegate

A delegate that specifies a method to call.

Implements

DoCallBack(CrossAppDomainDelegate)

Exceptions

ArgumentNullException

callBackDelegate is null.

Examples

The following sample demonstrates using a static DoCallBack method.

public ref class PingPong
{
private:
    static String^ greetings = "PONG!";

public:
    static void Main()
    {
        AppDomain^ otherDomain = AppDomain::CreateDomain("otherDomain");

        greetings = "PING!";
        MyCallBack();
        otherDomain->DoCallBack(gcnew CrossAppDomainDelegate(MyCallBack));

        // Output:
        //   PING! from defaultDomain
        //   PONG! from otherDomain
    }

    static void MyCallBack()
    {
        String^ name = AppDomain::CurrentDomain->FriendlyName;

        if (name == AppDomain::CurrentDomain->SetupInformation->ApplicationName)
        {
            name = "defaultDomain";
        }
        Console::WriteLine(greetings + " from " + name);
    }
};

int main()
{
   PingPong::Main();
}

static string greetings = "PONG!";

public static void Main()
{
    AppDomain otherDomain = AppDomain.CreateDomain("otherDomain");

    greetings = "PING!";
    MyCallBack();
    otherDomain.DoCallBack(new CrossAppDomainDelegate(MyCallBack));

    // Output:
    //   PING! from defaultDomain
    //   PONG! from otherDomain
}

static public void MyCallBack()
{
    string name = AppDomain.CurrentDomain.FriendlyName;

    if (name == AppDomain.CurrentDomain.SetupInformation.ApplicationName)
    {
        name = "defaultDomain";
    }
    Console.WriteLine(greetings + " from " + name);
}

open System

let mutable greetings = "PONG!"

let myCallBack () =
    let mutable name = AppDomain.CurrentDomain.FriendlyName

    if name = AppDomain.CurrentDomain.SetupInformation.ApplicationName then
        name <- "defaultDomain"
    printfn $"{greetings} from {name}"

let otherDomain = AppDomain.CreateDomain "otherDomain"
greetings <- "PING!"
myCallBack ()
otherDomain.DoCallBack(CrossAppDomainDelegate myCallBack)

// Output:
//   PING! from defaultDomain
//   PONG! from otherDomain

Public Module PingPong

    Private greetings As String = "PONG!"

    Sub Main()
        Dim otherDomain As AppDomain = AppDomain.CreateDomain("otherDomain")

        greetings = "PING!"
        MyCallBack()
        otherDomain.DoCallBack(AddressOf MyCallBack)

        ' Output:
        '   PING! from defaultDomain
        '   PONG! from otherDomain
     End Sub

     Sub MyCallBack()
        Dim name As String = AppDomain.CurrentDomain.FriendlyName
        If name = AppDomain.CurrentDomain.SetupInformation.ApplicationName Then
            name = "defaultDomain"
        End If
        Console.WriteLine(greetings + " from " + name)
     End Sub

End Module 'PingPong

The following sample demonstrates using the DoCallBack method by value.


[Serializable]
public ref class PingPong
{
private:
    String^ greetings;

public:
    PingPong()
    {
        greetings = "PING!";
    }

    static void Main()
    {
        AppDomain^ otherDomain = AppDomain::CreateDomain("otherDomain");

        PingPong^ pp = gcnew PingPong();
        pp->MyCallBack();
        pp->greetings = "PONG!";
        otherDomain->DoCallBack(gcnew CrossAppDomainDelegate( pp, &PingPong::MyCallBack));

        // Output:
        //   PING! from defaultDomain
        //   PONG! from otherDomain
    }

    void MyCallBack()
    {
        String^ name = AppDomain::CurrentDomain->FriendlyName;

        if (name == AppDomain::CurrentDomain->SetupInformation->ApplicationName)
        {
            name = "defaultDomain";
        }
        Console::WriteLine(greetings + " from " + name);
    }
};

int main()
{
   PingPong::Main();
}

[Serializable]
public class CallbackByValSnippet
{
    private string greetings = "PING!";

    public static void Main()
    {
        AppDomain otherDomain = AppDomain.CreateDomain("otherDomain");

        CallbackByValSnippet pp = new CallbackByValSnippet();
        pp.MyCallBack();
        pp.greetings = "PONG!";
        otherDomain.DoCallBack(new CrossAppDomainDelegate(pp.MyCallBack));

        // Output:
        //   PING! from defaultDomain
        //   PONG! from otherDomain
    }

    public void MyCallBack()
    {
        string name = AppDomain.CurrentDomain.FriendlyName;

        if (name == AppDomain.CurrentDomain.SetupInformation.ApplicationName)
        {
            name = "defaultDomain";
        }
        Console.WriteLine(greetings + " from " + name);
    }
}

open System

[<Serializable>]
type PingPong() as this =
    [<DefaultValue>]
    val mutable greetings: string
    do  
        this.greetings <- "PING!"

    member _.MyCallBack() =
        let mutable name = AppDomain.CurrentDomain.FriendlyName

        if name = AppDomain.CurrentDomain.SetupInformation.ApplicationName then
            name <- "defaultDomain"
        printfn $"{this.greetings} from {name}"

let otherDomain = AppDomain.CreateDomain "otherDomain"

let pp = PingPong()
pp.MyCallBack()
pp.greetings <- "PONG!"
otherDomain.DoCallBack(CrossAppDomainDelegate pp.MyCallBack)

// Output:
//   PING! from defaultDomain
//   PONG! from otherDomain

<Serializable> _
Public Class PingPong
     Private greetings As String = "PING!"

     Public Shared Sub Main()
        Dim otherDomain As AppDomain = AppDomain.CreateDomain("otherDomain")

        Dim pp As New PingPong()
        pp.MyCallBack()
        pp.greetings = "PONG!"
        otherDomain.DoCallBack(AddressOf pp.MyCallBack)

        ' Output:
        '   PING! from defaultDomain
        '   PONG! from otherDomain
    End Sub

    Public Sub MyCallBack()
        Dim name As String = AppDomain.CurrentDomain.FriendlyName
        If name = AppDomain.CurrentDomain.SetupInformation.ApplicationName Then
            name = "defaultDomain"
        End If
        Console.WriteLine(greetings + " from " + name)
    End Sub

End Class

The following sample demonstrates using the DoCallBack method by reference.

public ref class PingPong : public MarshalByRefObject
{
private:
   String^ greetings;

public:
    PingPong()
    {
        greetings = "PING!";
    }

    static void Main()
    {
        AppDomain^ otherDomain = AppDomain::CreateDomain("otherDomain");

        PingPong^ pp = gcnew PingPong();
        pp->MyCallBack();
        pp->greetings = "PONG!";
        otherDomain->DoCallBack(gcnew CrossAppDomainDelegate( pp, &PingPong::MyCallBack));

        // Output:
        //   PING! from defaultDomain
        //   PONG! from defaultDomain
    }

    // Callback will always execute within defaultDomain due to inheritance from
    // MarshalByRefObject
    void MyCallBack()
    {
        String^ name = AppDomain::CurrentDomain->FriendlyName;
        if (name == AppDomain::CurrentDomain->SetupInformation->ApplicationName)
        {
            name = "defaultDomain";
        }
        Console::WriteLine(greetings + " from " + name);
    }
};

int main()
{
   PingPong::Main();
}

public class CallbackByRefSnippet : MarshalByRefObject
{
    private string greetings = "PING!";

    public static void Main()
    {
        AppDomain otherDomain = AppDomain.CreateDomain("otherDomain");

        CallbackByRefSnippet pp = new CallbackByRefSnippet();
        pp.MyCallBack();
        pp.greetings = "PONG!";
        otherDomain.DoCallBack(new CrossAppDomainDelegate(pp.MyCallBack));

        // Output:
        //   PING! from defaultDomain
        //   PONG! from defaultDomain
    }

    // Callback will always execute within defaultDomain due to inheritance from
    // MarshalByRefObject
    public void MyCallBack()
    {
        string name = AppDomain.CurrentDomain.FriendlyName;
        if (name == AppDomain.CurrentDomain.SetupInformation.ApplicationName)
        {
            name = "defaultDomain";
        }
        Console.WriteLine(greetings + " from " + name);
    }
}

open System
type PingPong() as this =
    inherit MarshalByRefObject()
    [<DefaultValue>]
    val mutable greetings: string
    do  
        this.greetings <- "PING!"

    // Callback will always execute within defaultDomain due to inheritance from MarshalByRefObject
    member this.MyCallBack() =
        let mutable name = AppDomain.CurrentDomain.FriendlyName
        if name = AppDomain.CurrentDomain.SetupInformation.ApplicationName then
            name <- "defaultDomain"
        printfn $"{this.greetings} from {name}"

let otherDomain = AppDomain.CreateDomain "otherDomain"

let pp = new PingPong()
pp.MyCallBack()
pp.greetings <- "PONG!"
otherDomain.DoCallBack(CrossAppDomainDelegate pp.MyCallBack)

// Output:
//   PING! from defaultDomain
//   PONG! from defaultDomain

Public Class PingPong
    Inherits MarshalByRefObject

    Private greetings As String = "PING!"
   
    Public Shared Sub Main()
        Dim otherDomain As AppDomain = AppDomain.CreateDomain("otherDomain")

        Dim pp As New PingPong()
        pp.MyCallBack()
        pp.greetings = "PONG!"
        otherDomain.DoCallBack(AddressOf pp.MyCallBack)

        ' Output:
        '   PING! from default domain
        '   PONG! from default domain
     End Sub

    ' Callback will always execute within defaultDomain due to inheritance from
    ' MarshalByRefObject
    Public Sub MyCallBack()
        Dim name As String = AppDomain.CurrentDomain.FriendlyName
        If name = AppDomain.CurrentDomain.SetupInformation.ApplicationName Then
            name = "defaultDomain"
        End If
        Console.WriteLine((greetings + " from " + name))
    End Sub

End Class

Remarks

callBackDelegate can specify a marshal-by-value, MarshalByRefObject, or ContextBoundObject.

Applies to

Jaa