Visualizzazione delle informazioni sul tipoViewing Type Information

La classe System.Type è fondamentale per la reflection.The System.Type class is central to reflection. Quando la reflection lo richiede, Common Language Runtime crea l'oggetto Type relativo a un tipo caricato.The common language runtime creates the Type for a loaded type when reflection requests it. Per ottenere informazioni sul tipo, è possibile usare metodi, campi, proprietà e classi nidificate dell'oggetto Type.You can use a Type object's methods, fields, properties, and nested classes to find out everything about that type.

Usare Assembly.GetType o Assembly.GetTypes per ottenere oggetti Type da assembly che non sono stati caricati, passando il nome del tipo o dei tipi desiderati.Use Assembly.GetType or Assembly.GetTypes to obtain Type objects from assemblies that have not been loaded, passing in the name of the type or types you want. Usare Type.GetType per ottenere oggetti Type da un assembly già caricato.Use Type.GetType to get the Type objects from an assembly that is already loaded. Usare Module.GetType e Module.GetTypes per ottenere gli oggetti Type dei moduli.Use Module.GetType and Module.GetTypes to obtain module Type objects.

Nota

Se si vuole esaminare e modificare tipi e metodi generici, vedere le altre informazioni disponibili in Reflection e tipi generici e Procedura: Esaminare e creare istanze di tipi generici tramite reflection.If you want to examine and manipulate generic types and methods, please see the additional information provided in Reflection and Generic Types and How to: Examine and Instantiate Generic Types with Reflection.

L'esempio seguente illustra la sintassi necessaria per ottenere il modulo e l'oggetto Assembly per un assembly.The following example shows the syntax necessary to get the Assembly object and module for an assembly.

// Gets the mscorlib assembly in which the object is defined.
Assembly^ a = Object::typeid->Module->Assembly;
// Gets the mscorlib assembly in which the object is defined.
Assembly a = typeof(object).Module.Assembly;
' Gets the mscorlib assembly in which the object is defined.
Dim a As Assembly = GetType(Object).Module.Assembly

L'esempio seguente descrive come ottenere oggetti Type per un assembly caricato.The following example demonstrates getting Type objects from a loaded assembly.

// Loads an assembly using its file name.
Assembly^ a = Assembly::LoadFrom("MyExe.exe");
// Gets the type names from the assembly.
array<Type^>^ types2 = a->GetTypes();
for each (Type^ t in types2)
{
    Console::WriteLine(t->FullName);
}
// Loads an assembly using its file name.
Assembly a = Assembly.LoadFrom("MyExe.exe");
// Gets the type names from the assembly.
Type[] types2 = a.GetTypes();
foreach (Type t in types2)
{
    Console.WriteLine(t.FullName);
}
' Loads an assembly using its file name.
Dim a As Assembly = Assembly.LoadFrom("MyExe.exe")
' Gets the type names from the assembly.
Dim types2() As Type = a.GetTypes()
For Each t As Type In types2
    Console.WriteLine(t.FullName)
Next t

Dopo aver ottenuto un oggetto Type, è possibile ottenere informazioni sui membri del tipo in modi diversi.Once you obtain a Type, there are many ways you can discover information about the members of that type. Ad esempio, per ottenere informazioni su tutti i membri del tipo è possibile chiamare il metodo Type.GetMembers che ottiene una matrice di oggetti MemberInfo ognuno dei quali descrive un membro del tipo corrente.For example, you can find out about all the type's members by calling the Type.GetMembers method, which obtains an array of MemberInfo objects describing each of the members of the current type.

È anche possibile usare i metodi nella classe Type per recuperare informazioni su uno o più costruttori, metodi, eventi, campi o proprietà di cui si specifica il nome.You can also use methods on the Type class to retrieve information about one or more constructors, methods, events, fields, or properties that you specify by name. Ad esempio, Type.GetConstructor incapsula uno costruttore specifico della classe corrente.For example, Type.GetConstructor encapsulates a specific constructor of the current class.

Se è presente un oggetto Type è possibile usare la proprietà Type.Module per ottenere un oggetto che incapsula il modulo contenente il tipo.If you have a Type, you can use the Type.Module property to obtain an object that encapsulates the module containing that type. Usare la proprietà Module.Assembly per individuare un oggetto che incapsula l'assembly contenente il modulo.Use the Module.Assembly property to locate an object that encapsulates the assembly containing the module. Per ottenere direttamente l'assembly che incapsula il tipo, usare la proprietà Type.Assembly.You can obtain the assembly that encapsulates the type directly by using the Type.Assembly property.

System.Type e ConstructorInfoSystem.Type and ConstructorInfo

L'esempio seguente illustra come elencare i costruttori di una classe, nel caso specifico la classe String.The following example shows how to list the constructors for a class, in this case, the String class.

// This program lists all the public constructors
// of the System.String class.
using namespace System;
using namespace System::Reflection;

class ListMembers
{
public:
    static void Main()
    {
        Type^ t = System::String::typeid;
        Console::WriteLine ("Listing all the public constructors of the {0} type", t);
        // Constructors.
        array<ConstructorInfo^>^ ci = t->GetConstructors(BindingFlags::Public | BindingFlags::Instance);
        Console::WriteLine ("//Constructors");
        PrintMembers(ci);
    }

    static void PrintMembers(array<MemberInfo^>^ ms)
    {
        for each (MemberInfo^ m in ms)
        {
            Console::WriteLine ("{0}{1}", "     ", m);
        }
        Console::WriteLine();
    }
};

int main()
{
    ListMembers::Main();
}
// This program lists all the public constructors
// of the System.String class.
using System;
using System.Reflection;

class ListMembers
{
    public static void Main()
    {
        Type t = typeof(System.String);
        Console.WriteLine("Listing all the public constructors of the {0} type", t);
        // Constructors.
        ConstructorInfo[] ci = t.GetConstructors(BindingFlags.Public | BindingFlags.Instance);
        Console.WriteLine("//Constructors");
        PrintMembers(ci);
    }

    public static void PrintMembers(MemberInfo[] ms)
    {
        foreach (MemberInfo m in ms)
        {
            Console.WriteLine("{0}{1}", "     ", m);
        }
        Console.WriteLine();
    }
}
' This program lists all the public constructors
' of the System.String class.

Imports System.Reflection

Class ListMembers
    Public Shared Sub Main()
        Dim t As Type = GetType(String)
        Console.WriteLine("Listing all the public constructors of the {0} type", t)
        ' Constructors.
        Dim ci As ConstructorInfo() = t.GetConstructors((BindingFlags.Public Or BindingFlags.Instance))
        Console.WriteLine("//Constructors")
        PrintMembers(ci)
    End Sub
    Public Shared Sub PrintMembers(ms() As MemberInfo)
        Dim m As MemberInfo
        For Each m In ms
            Console.WriteLine("{0}{1}", "     ", m)
        Next m
        Console.WriteLine()
    End Sub
End Class

MemberInfo, MethodInfo, FieldInfo e PropertyInfoMemberInfo, MethodInfo, FieldInfo, and PropertyInfo

Per ottenere informazioni su metodi, proprietà, eventi e campi del tipo, usare gli oggetti MemberInfo, MethodInfo, FieldInfo o PropertyInfo.Obtain information about the type's methods, properties, events, and fields using MemberInfo, MethodInfo, FieldInfo, or PropertyInfo objects.

L'esempio seguente usa MemberInfo per elencare il numero di membri della classe System.IO.File e usa la proprietà IsPublic per determinare la visibilità della classe.The following example uses MemberInfo to list the number of members in the System.IO.File class and uses the IsPublic property to determine the visibility of the class.

using namespace System;
using namespace System::IO;
using namespace System::Reflection;

public ref class Mymemberinfo
{
public:
    static void Main()
    {
        Console::WriteLine ("\nReflection.MemberInfo");
        // Gets the Type and MemberInfo.
        Type^ MyType = Type::GetType("System.IO.File");
        array<MemberInfo^>^ Mymemberinfoarray = MyType->GetMembers();
        // Gets and displays the DeclaringType method.
        Console::WriteLine("\nThere are {0} members in {1}.",
            Mymemberinfoarray->Length, MyType->FullName);
        Console::WriteLine("{0}.", MyType->FullName);
        if (MyType->IsPublic)
        {
            Console::WriteLine("{0} is public.", MyType->FullName);
        }
    }
};

int main()
{
    Mymemberinfo::Main();
}
using System;
using System.IO;
using System.Reflection;

class Mymemberinfo
{
    public static void Main()
    {
        Console.WriteLine ("\nReflection.MemberInfo");
        // Gets the Type and MemberInfo.
        Type MyType = Type.GetType("System.IO.File");
        MemberInfo[] Mymemberinfoarray = MyType.GetMembers();
        // Gets and displays the DeclaringType method.
        Console.WriteLine("\nThere are {0} members in {1}.",
            Mymemberinfoarray.Length, MyType.FullName);
        Console.WriteLine("{0}.", MyType.FullName);
        if (MyType.IsPublic)
        {
            Console.WriteLine("{0} is public.", MyType.FullName);
        }
    }
}
Imports System.IO
Imports System.Reflection

Class Mymemberinfo
    Public Shared Sub Main()
        Console.WriteLine ("\nReflection.MemberInfo")
        ' Gets the Type and MemberInfo.
        Dim MyType As Type = Type.GetType("System.IO.File")
        Dim Mymemberinfoarray() As MemberInfo = MyType.GetMembers()
        ' Gets and displays the DeclaringType method.
        Console.WriteLine("\nThere are {0} members in {1}.",
            Mymemberinfoarray.Length, MyType.FullName)
        Console.WriteLine("{0}.", MyType.FullName)
        If MyType.IsPublic
            Console.WriteLine("{0} is public.", MyType.FullName)
        End If
    End Sub
End Class

L'esempio seguente analizza il tipo del membro specificato.The following example investigates the type of the specified member. Viene eseguita una reflection su un membro della classe MemberInfo e ne viene elencato il tipo.It performs reflection on a member of the MemberInfo class, and lists its type.

// This code displays information about the GetValue method of FieldInfo.
using namespace System;
using namespace System::Reflection;

public ref class MyMethodInfo
{
public:
    static int Main()
    {
        Console::WriteLine("Reflection.MethodInfo");
        // Gets and displays the Type.
        Type^ MyType = Type::GetType("System.Reflection.FieldInfo");
        // Specifies the member for which you want type information.
        MethodInfo^ Mymethodinfo = MyType->GetMethod("GetValue");
        Console::WriteLine(MyType->FullName + "." + Mymethodinfo->Name);
        // Gets and displays the MemberType property.
        MemberTypes Mymembertypes = Mymethodinfo->MemberType;
        if (MemberTypes::Constructor == Mymembertypes)
        {
            Console::WriteLine("MemberType is of type All");
        }
        else if (MemberTypes::Custom == Mymembertypes)
        {
            Console::WriteLine("MemberType is of type Custom");
        }
        else if (MemberTypes::Event == Mymembertypes)
        {
            Console::WriteLine("MemberType is of type Event");
        }
        else if (MemberTypes::Field == Mymembertypes)
        {
            Console::WriteLine("MemberType is of type Field");
        }
        else if (MemberTypes::Method == Mymembertypes)
        {
            Console::WriteLine("MemberType is of type Method");
        }
        else if (MemberTypes::Property == Mymembertypes)
        {
            Console::WriteLine("MemberType is of type Property");
        }
        else if (MemberTypes::TypeInfo == Mymembertypes)
        {
            Console::WriteLine("MemberType is of type TypeInfo");
        }
        return 0;
    }
};

int main()
{
    MyMethodInfo::Main();
}
// This code displays information about the GetValue method of FieldInfo.
using System;
using System.Reflection;

class MyMethodInfo
{
    public static int Main()
    {
        Console.WriteLine("Reflection.MethodInfo");
        // Gets and displays the Type.
        Type MyType = Type.GetType("System.Reflection.FieldInfo");
        // Specifies the member for which you want type information.
        MethodInfo Mymethodinfo = MyType.GetMethod("GetValue");
        Console.WriteLine(MyType.FullName + "." + Mymethodinfo.Name);
        // Gets and displays the MemberType property.
        MemberTypes Mymembertypes = Mymethodinfo.MemberType;
        if (MemberTypes.Constructor == Mymembertypes)
        {
            Console.WriteLine("MemberType is of type All");
        }
        else if (MemberTypes.Custom == Mymembertypes)
        {
            Console.WriteLine("MemberType is of type Custom");
        }
        else if (MemberTypes.Event == Mymembertypes)
        {
            Console.WriteLine("MemberType is of type Event");
        }
        else if (MemberTypes.Field == Mymembertypes)
        {
            Console.WriteLine("MemberType is of type Field");
        }
        else if (MemberTypes.Method == Mymembertypes)
        {
            Console.WriteLine("MemberType is of type Method");
        }
        else if (MemberTypes.Property == Mymembertypes)
        {
            Console.WriteLine("MemberType is of type Property");
        }
        else if (MemberTypes.TypeInfo == Mymembertypes)
        {
            Console.WriteLine("MemberType is of type TypeInfo");
        }
        return 0;
    }
}
' This code displays information about the GetValue method of FieldInfo.
Imports System.Reflection
Class MyMethodInfo
    Public Shared Sub Main()
        Console.WriteLine("Reflection.MethodInfo")
        ' Gets and displays the Type.
        Dim MyType As Type = Type.GetType("System.Reflection.FieldInfo")
        ' Specifies the member for which you want type information.
        Dim Mymethodinfo As MethodInfo = MyType.GetMethod("GetValue")
        Console.WriteLine((MyType.FullName & "." & Mymethodinfo.Name))
        ' Gets and displays the MemberType property.
        Dim Mymembertypes As MemberTypes = Mymethodinfo.MemberType
        If MemberTypes.Constructor = Mymembertypes Then
            Console.WriteLine("MemberType is of type All")
        ElseIf MemberTypes.Custom = Mymembertypes Then
            Console.WriteLine("MemberType is of type Custom")
        ElseIf MemberTypes.Event = Mymembertypes Then
            Console.WriteLine("MemberType is of type Event")
        ElseIf MemberTypes.Field = Mymembertypes Then
            Console.WriteLine("MemberType is of type Field")
        ElseIf MemberTypes.Method = Mymembertypes Then
            Console.WriteLine("MemberType is of type Method")
        ElseIf MemberTypes.Property = Mymembertypes Then
            Console.WriteLine("MemberType is of type Property")
        ElseIf MemberTypes.TypeInfo = Mymembertypes Then
            Console.WriteLine("MemberType is of type TypeInfo")
        End If
        Return
    End Sub
End Class

L'esempio seguente usa tutte le classi *Info di Reflection con BindingFlags per elencare tutti i membri (costruttori, campi, proprietà, eventi e metodi) della classe specificata, distinguendo tra membri statici e di istanza.The following example uses all the Reflection *Info classes along with BindingFlags to list all the members (constructors, fields, properties, events, and methods) of the specified class, dividing the members into static and instance categories.

// This program lists all the members of the
// System.IO.BufferedStream class.
using namespace System;
using namespace System::IO;
using namespace System::Reflection;

public ref class ListMembers
{
public:
    static void Main()
    {
        // Specifies the class.
        Type^ t = System::IO::BufferedStream::typeid;
        Console::WriteLine("Listing all the members (public and non public) of the {0} type", t);

        // Lists static fields first.
        array<FieldInfo^>^ fi = t->GetFields(BindingFlags::Static |
            BindingFlags::NonPublic | BindingFlags::Public);
        Console::WriteLine("// Static Fields");
        PrintMembers(fi);

        // Static properties.
        array<PropertyInfo^>^ pi = t->GetProperties(BindingFlags::Static |
            BindingFlags::NonPublic | BindingFlags::Public);
        Console::WriteLine("// Static Properties");
        PrintMembers(pi);

        // Static events.
        array<EventInfo^>^ ei = t->GetEvents(BindingFlags::Static |
            BindingFlags::NonPublic | BindingFlags::Public);
        Console::WriteLine("// Static Events");
        PrintMembers(ei);

        // Static methods.
        array<MethodInfo^>^ mi = t->GetMethods (BindingFlags::Static |
            BindingFlags::NonPublic | BindingFlags::Public);
        Console::WriteLine("// Static Methods");
        PrintMembers(mi);

        // Constructors.
        array<ConstructorInfo^>^ ci = t->GetConstructors(BindingFlags::Instance |
            BindingFlags::NonPublic | BindingFlags::Public);
        Console::WriteLine("// Constructors");
        PrintMembers(ci);

        // Instance fields.
        fi = t->GetFields(BindingFlags::Instance | BindingFlags::NonPublic |
            BindingFlags::Public);
        Console::WriteLine("// Instance Fields");
        PrintMembers(fi);

        // Instance properites.
        pi = t->GetProperties(BindingFlags::Instance | BindingFlags::NonPublic |
            BindingFlags::Public);
        Console::WriteLine ("// Instance Properties");
        PrintMembers(pi);

        // Instance events.
        ei = t->GetEvents(BindingFlags::Instance | BindingFlags::NonPublic |
            BindingFlags::Public);
        Console::WriteLine("// Instance Events");
        PrintMembers(ei);

        // Instance methods.
        mi = t->GetMethods(BindingFlags::Instance | BindingFlags::NonPublic
            | BindingFlags::Public);
        Console::WriteLine("// Instance Methods");
        PrintMembers(mi);

        Console::WriteLine("\r\nPress ENTER to exit.");
        Console::Read();
    }

    static void PrintMembers(array<MemberInfo^>^ ms)
    {
        for each (MemberInfo^ m in ms)
        {
            Console::WriteLine ("{0}{1}", "     ", m);
        }
        Console::WriteLine();
    }
};

int main()
{
    ListMembers::Main();
}
// This program lists all the members of the
// System.IO.BufferedStream class.
using System;
using System.IO;
using System.Reflection;

class ListMembers
{
    public static void Main()
    {
        // Specifies the class.
        Type t = typeof(System.IO.BufferedStream);
        Console.WriteLine("Listing all the members (public and non public) of the {0} type", t);

        // Lists static fields first.
        FieldInfo[] fi = t.GetFields(BindingFlags.Static |
            BindingFlags.NonPublic | BindingFlags.Public);
        Console.WriteLine("// Static Fields");
        PrintMembers(fi);

        // Static properties.
        PropertyInfo[] pi = t.GetProperties(BindingFlags.Static |
            BindingFlags.NonPublic | BindingFlags.Public);
        Console.WriteLine("// Static Properties");
        PrintMembers(pi);

        // Static events.
        EventInfo[] ei = t.GetEvents(BindingFlags.Static |
            BindingFlags.NonPublic | BindingFlags.Public);
        Console.WriteLine("// Static Events");
        PrintMembers(ei);

        // Static methods.
        MethodInfo[] mi = t.GetMethods (BindingFlags.Static |
            BindingFlags.NonPublic | BindingFlags.Public);
        Console.WriteLine("// Static Methods");
        PrintMembers(mi);

        // Constructors.
        ConstructorInfo[] ci = t.GetConstructors(BindingFlags.Instance |
            BindingFlags.NonPublic | BindingFlags.Public);
        Console.WriteLine("// Constructors");
        PrintMembers(ci);

        // Instance fields.
        fi = t.GetFields(BindingFlags.Instance | BindingFlags.NonPublic |
            BindingFlags.Public);
        Console.WriteLine("// Instance Fields");
        PrintMembers(fi);

        // Instance properites.
        pi = t.GetProperties(BindingFlags.Instance | BindingFlags.NonPublic |
            BindingFlags.Public);
        Console.WriteLine ("// Instance Properties");
        PrintMembers(pi);

        // Instance events.
        ei = t.GetEvents(BindingFlags.Instance | BindingFlags.NonPublic |
            BindingFlags.Public);
        Console.WriteLine("// Instance Events");
        PrintMembers(ei);

        // Instance methods.
        mi = t.GetMethods(BindingFlags.Instance | BindingFlags.NonPublic
            | BindingFlags.Public);
        Console.WriteLine("// Instance Methods");
        PrintMembers(mi);

        Console.WriteLine("\r\nPress ENTER to exit.");
        Console.Read();
    }

    public static void PrintMembers (MemberInfo [] ms)
    {
        foreach (MemberInfo m in ms)
        {
            Console.WriteLine ("{0}{1}", "     ", m);
        }
        Console.WriteLine();
    }
}
' This program lists all the members of the
' System.IO.BufferedStream class.
Imports System.IO
Imports System.Reflection

Class ListMembers
    Public Shared Sub Main()
        ' Specifies the class.
        Dim t As Type = GetType(System.IO.BufferedStream)
        Console.WriteLine("Listing all the members (public and non public) of the {0} type", t)
        ' Lists static fields first.
        Dim fi As FieldInfo() = t.GetFields((BindingFlags.Static Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Static Fields")
        PrintMembers(fi)
        ' Static properties.
        Dim pi As PropertyInfo() = t.GetProperties((BindingFlags.Static Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Static Properties")
        PrintMembers(pi)
        ' Static events.
        Dim ei As EventInfo() = t.GetEvents((BindingFlags.Static Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Static Events")
        PrintMembers(ei)
        ' Static methods.
        Dim mi As MethodInfo() = t.GetMethods((BindingFlags.Static Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Static Methods")
        PrintMembers(mi)
        ' Constructors.
        Dim ci As ConstructorInfo() = t.GetConstructors((BindingFlags.Instance Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Constructors")
        PrintMembers(ci)
        ' Instance fields.
        fi = t.GetFields((BindingFlags.Instance Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Instance Fields")
        PrintMembers(fi)
        ' Instance properites.
        pi = t.GetProperties((BindingFlags.Instance Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Instance Properties")
        PrintMembers(pi)
        ' Instance events.
        ei = t.GetEvents((BindingFlags.Instance Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Instance Events")
        PrintMembers(ei)
        ' Instance methods.
        mi = t.GetMethods((BindingFlags.Instance Or BindingFlags.NonPublic Or BindingFlags.Public))
        Console.WriteLine("// Instance Methods")
        PrintMembers(mi)
        Console.WriteLine(ControlChars.CrLf & "Press ENTER to exit.")
        Console.Read()
    End Sub

    Public Shared Sub PrintMembers(ms() As MemberInfo)
        Dim m As MemberInfo
        For Each m In  ms
            Console.WriteLine("{0}{1}", "     ", m)
        Next m
        Console.WriteLine()
    End Sub
End Class

Vedere ancheSee also