AppDomain.TypeResolve Événement

Définition

Espace de noms:

System

Assembly:

System.Runtime.dll

Source:

AppDomain.cs

Se produit quand la résolution d'un type échoue.

public:
 event ResolveEventHandler ^ TypeResolve;

public event ResolveEventHandler? TypeResolve;

member this.TypeResolve : ResolveEventHandler 

Public Custom Event TypeResolve As ResolveEventHandler 

Type d'événement

ResolveEventHandler

Exemples

L’exemple suivant illustre l’événement TypeResolve .

Pour que cet exemple de code s’exécute, vous devez fournir le nom complet de l’assembly. Pour plus d’informations sur la façon d’obtenir le nom complet de l’assembly, consultez Noms d’assembly.

#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>

using namespace System;
using namespace System::Reflection;
using namespace System::Reflection::Emit;

ref class Test
{
private:
    static Assembly^ HandleTypeResolve(Object^ sender, ResolveEventArgs^ args) 
    {
        Console::WriteLine("TypeResolve event handler.");

        // Save the dynamic assembly, and then load it using its
        // display name. Return the loaded assembly.
        //
        ab->Save(moduleName);
        return Assembly::Load(ab->FullName); 
    }

    // For this code example, the following information needs to be
    // available to both Demo and the HandleTypeResolve event
    // handler:
    static AssemblyBuilder^ ab;
    static String^ moduleName;

public:
    static void Demo() 
    {
        AppDomain^ currDom = AppDomain::CurrentDomain;

        // Create a dynamic assembly with one module, to be saved to 
        // disk (AssemblyBuilderAccess::Save).
        // 
        AssemblyName^ aName = gcnew AssemblyName();
        aName->Name = "Transient";
        moduleName = aName->Name + ".dll";
        ab = currDom->DefineDynamicAssembly(aName,
            AssemblyBuilderAccess::Save);
        ModuleBuilder^ mb = ab->DefineDynamicModule(aName->Name, moduleName);

        // The dynamic assembly has just one dummy type, to demonstrate
        // type resolution.
        TypeBuilder^ tb = mb->DefineType("Example");
        tb->CreateType();


        // First, try to load the type without saving the dynamic 
        // assembly and without hooking up the TypeResolve event. The
        // type cannot be loaded.
        try
        {
            Type^ temp = Type::GetType("Example", true);
            Console::WriteLine("Loaded type {0}.", temp);
        }
        catch (TypeLoadException^)
        {
            Console::WriteLine("Loader could not resolve the type.");
        }

        // Hook up the TypeResolve event.
        //      
        currDom->TypeResolve += 
            gcnew ResolveEventHandler(HandleTypeResolve);

        // Now try to load the type again. The TypeResolve event is 
        // raised, the dynamic assembly is saved, and the dummy type is
        // loaded successfully. Display it to the console, and create
        // an instance.
        Type^ t = Type::GetType("Example", true);
        Console::WriteLine("Loaded type \"{0}\".", t);
        Object^ o = Activator::CreateInstance(t);
    }
};

void main()
{
    Test::Demo();
}

/* This code example produces the following output:

Loader could not resolve the type.
TypeResolve event handler.
Loaded type "Example".
 */

using System;
using System.Reflection;
using System.Reflection.Emit;

class Test
{
    // For this code example, the following information needs to be
    // available to both Main and the HandleTypeResolve event
    // handler:
    private static AssemblyBuilder ab;
    private static string moduleName;

    public static void Main()
    {
        AppDomain currDom = AppDomain.CurrentDomain;

        // Create a dynamic assembly with one module, to be saved to
        // disk (AssemblyBuilderAccess.Save).
        //
        AssemblyName aName = new AssemblyName();
        aName.Name = "Transient";
        moduleName = aName.Name + ".dll";
        ab = currDom.DefineDynamicAssembly(aName,
            AssemblyBuilderAccess.Save);
        ModuleBuilder mb = ab.DefineDynamicModule(aName.Name, moduleName);

        // The dynamic assembly has just one dummy type, to demonstrate
        // type resolution.
        TypeBuilder tb = mb.DefineType("Example");
        tb.CreateType();

        // First, try to load the type without saving the dynamic
        // assembly and without hooking up the TypeResolve event. The
        // type cannot be loaded.
        try
        {
            Type temp = Type.GetType("Example", true);
            Console.WriteLine("Loaded type {0}.", temp);
        }
        catch (TypeLoadException)
        {
            Console.WriteLine("Loader could not resolve the type.");
        }

        // Hook up the TypeResolve event.
        //
        currDom.TypeResolve +=
            new ResolveEventHandler(HandleTypeResolve);

        // Now try to load the type again. The TypeResolve event is
        // raised, the dynamic assembly is saved, and the dummy type is
        // loaded successfully. Display it to the console, and create
        // an instance.
        Type t = Type.GetType("Example", true);
        Console.WriteLine("Loaded type \"{0}\".", t);
        Object o = Activator.CreateInstance(t);
    }

    static Assembly HandleTypeResolve(object sender, ResolveEventArgs args)
    {
        Console.WriteLine("TypeResolve event handler.");

        // Save the dynamic assembly, and then load it using its
        // display name. Return the loaded assembly.
        //
        ab.Save(moduleName);
        return Assembly.Load(ab.FullName);
    }
}

/* This code example produces the following output:

Loader could not resolve the type.
TypeResolve event handler.
Loaded type "Example".
 */

open System
open System.Reflection
open System.Reflection.Emit

let currDom = AppDomain.CurrentDomain

// Create a dynamic assembly with one module, to be saved to
// disk (AssemblyBuilderAccess.Save).
//
let aName = AssemblyName()
aName.Name <- "Transient"
let moduleName = aName.Name + ".dll"
let ab = currDom.DefineDynamicAssembly(aName, AssemblyBuilderAccess.Save)

let handleTypeResolve _ _ =
    printfn "TypeResolve event handler."

    // Save the dynamic assembly, and then load it using its
    // display name. Return the loaded assembly.
    ab.Save moduleName
    Assembly.Load ab.FullName

let mb = ab.DefineDynamicModule(aName.Name, moduleName)

// The dynamic assembly has just one dummy type, to demonstrate
// type resolution.
let tb = mb.DefineType "Example"
tb.CreateType() |> ignore

// First, try to load the type without saving the dynamic
// assembly and without hooking up the TypeResolve event. The
// type cannot be loaded.
try
    let temp = Type.GetType("Example", true)
    printfn $"Loaded type {temp}."
with :? TypeLoadException ->
    printfn "Loader could not resolve the type."

// Hook up the TypeResolve event.
//
currDom.add_TypeResolve(ResolveEventHandler handleTypeResolve)

// Now try to load the type again. The TypeResolve event is
// raised, the dynamic assembly is saved, and the dummy type is
// loaded successfully. Display it to the console, and create
// an instance.
let t = Type.GetType("Example", true)
printfn $"Loaded type \"{t}\"."
let o = Activator.CreateInstance t

(* This code example produces the following output:

Loader could not resolve the type.
TypeResolve event handler.
Loaded type "Example".
 *)

Option Strict On
Option Explicit On

Imports System.Reflection
Imports System.Reflection.Emit

Module Test

    ' For this code example, the following information needs to be
    ' available to both Main and the HandleTypeResolve event
    ' handler:
    Private ab As AssemblyBuilder
    Private moduleName As String

    Sub Main() 
    
        Dim currDom As AppDomain = AppDomain.CurrentDomain

        ' Create a dynamic assembly with one module, to be saved to 
        ' disk (AssemblyBuilderAccess.Save).
        ' 
        Dim aName As AssemblyName = new AssemblyName()
        aName.Name = "Transient"
        moduleName = aName.Name + ".dll"
        ab = currDom.DefineDynamicAssembly(aName, _
            AssemblyBuilderAccess.Save)
        Dim mb As ModuleBuilder = _
            ab.DefineDynamicModule(aName.Name, moduleName)

        ' The dynamic assembly has just one dummy type, to demonstrate
        ' type resolution.
        Dim tb As TypeBuilder = mb.DefineType("Example")
        tb.CreateType()


        ' First, try to load the type without saving the dynamic 
        ' assembly and without hooking up the TypeResolve event. The
        ' type cannot be loaded.
        Try
            Dim temp As Type = Type.GetType("Example", true)
            Console.WriteLine("Loaded type {0}.", temp)
        Catch ex As TypeLoadException
            Console.WriteLine("Loader could not resolve the type.")
        End Try

        ' Hook up the TypeResolve event.
        '      
        AddHandler currDom.TypeResolve, AddressOf HandleTypeResolve

        ' Now try to load the type again. The TypeResolve event is 
        ' raised, the dynamic assembly is saved, and the dummy type is
        ' loaded successfully. Display it to the console, and create
        ' an instance.
        Dim t As Type = Type.GetType("Example", true)
        Console.WriteLine("Loaded type ""{0}"".", t)
        Dim o As Object = Activator.CreateInstance(t)
    End Sub

    Private Function HandleTypeResolve(ByVal sender As Object, _
        ByVal e As ResolveEventArgs) As [Assembly]
    
        Console.WriteLine("TypeResolve event handler.")

        ' Save the dynamic assembly, and then load it using its
        ' display name. Return the loaded assembly.
        '
        ab.Save(moduleName)
        Return [Assembly].Load(ab.FullName) 
    End Function
End Module

' This code example produces the following output:
'
'Loader could not resolve the type.
'TypeResolve event handler.
'Loaded type "Example".
'

Remarques

L’événement TypeResolve se produit lorsque le Common Language Runtime ne parvient pas à déterminer l’assembly qui peut créer le type demandé. Cela peut se produire si le type est défini dans un assembly dynamique ou si le type n’est pas défini dans un assembly dynamique, mais que le runtime ne sait pas dans quel assembly le type est défini. Cette dernière situation peut se produire lorsque Type.GetType est appelé avec un nom de type qui n’est pas qualifié avec le nom de l’assembly.

pour ResolveEventHandler cet événement peut tenter de localiser et de créer le type.

Toutefois, l’événement TypeResolve ne se produit pas si le runtime sait qu’il n’est pas possible de trouver un type dans certains assemblys. Par exemple, cet événement ne se produit pas si le type est introuvable dans un assembly statique, car le runtime sait que les types ne peuvent pas être ajoutés dynamiquement aux assemblys statiques.

À compter du .NET Framework 4, la ResolveEventArgs.RequestingAssembly propriété contient l’assembly qui a demandé le type. Pour plus d'informations, consultez ResolveEventArgs.RequestingAssembly.

Pour inscrire un gestionnaire d’événements pour cet événement, vous devez disposer des autorisations requises, ou un SecurityException est levée.

Pour plus d'informations sur la gestion des événements, voir gestion et déclenchement d’événements.

Voir aussi

• RequestingAssembly