Assembly Class

Definition

Namespace:

System.Reflection

Assembly:

System.Runtime.dll

Source:

Assembly.cs

Represents an assembly, which is a reusable, versionable, and self-describing building block of a common language runtime application.

public ref class Assembly abstract : System::Reflection::ICustomAttributeProvider, System::Runtime::Serialization::ISerializable

public abstract class Assembly : System.Reflection.ICustomAttributeProvider, System.Runtime.Serialization.ISerializable

type Assembly = class
    interface ICustomAttributeProvider
    interface ISerializable

Public MustInherit Class Assembly
Implements ICustomAttributeProvider, ISerializable

Inheritance

Object

Assembly

Derived

System.Reflection.Emit.AssemblyBuilder

Implements

ICustomAttributeProvider ISerializable

Examples

The following code example shows how to obtain the currently executing assembly, create an instance of a type contained in that assembly, and invoke one of the type's methods with late binding. For this purpose, the code example defines a class named Example, with a method named SampleMethod. The constructor of the class accepts an integer, which is used to compute the return value of the method.

The code example also demonstrates the use of the GetName method to obtain an AssemblyName object that can be used to parse the full name of the assembly. The example displays the version number of the assembly, the CodeBase property, and the EntryPoint property.

using namespace System;
using namespace System::Reflection;
using namespace System::Security::Permissions;

[assembly:AssemblyVersionAttribute("1.0.2000.0")];

public ref class Example
{
private: 
    int factor;

public:
    Example(int f)
    {
        factor = f;
    }

    int SampleMethod(int x) 
    { 
        Console::WriteLine("\nExample->SampleMethod({0}) executes.", x);
        return x * factor;
    }
};

void main()
{
    Assembly^ assem = Example::typeid->Assembly;

    Console::WriteLine("Assembly Full Name:");
    Console::WriteLine(assem->FullName);

    // The AssemblyName type can be used to parse the full name.
    AssemblyName^ assemName = assem->GetName();
    Console::WriteLine("\nName: {0}", assemName->Name);
    Console::WriteLine("Version: {0}.{1}", 
        assemName->Version->Major, assemName->Version->Minor);

    Console::WriteLine("\nAssembly CodeBase:");
    Console::WriteLine(assem->CodeBase);

    // Create an object from the assembly, passing in the correct number and
    // type of arguments for the constructor.
    Object^ o = assem->CreateInstance("Example", false, 
        BindingFlags::ExactBinding, 
        nullptr, gcnew array<Object^> { 2 }, nullptr, nullptr);

    // Make a late-bound call to an instance method of the object.    
    MethodInfo^ m = assem->GetType("Example")->GetMethod("SampleMethod");
    Object^ ret = m->Invoke(o, gcnew array<Object^> { 42 });
    Console::WriteLine("SampleMethod returned {0}.", ret);

    Console::WriteLine("\nAssembly entry point:");
    Console::WriteLine(assem->EntryPoint);
}

/* This code example produces output similar to the following:

Assembly Full Name:
source, Version=1.0.2000.0, Culture=neutral, PublicKeyToken=null

Name: source
Version: 1.0

Assembly CodeBase:
file:///C:/sdtree/AssemblyClass/cpp/source.exe

Example->SampleMethod(42) executes.
SampleMethod returned 84.

Assembly entry point:
UInt32 _mainCRTStartup()
 */

using System;
using System.Reflection;
using System.Security.Permissions;

[assembly:AssemblyVersionAttribute("1.0.2000.0")]

public class Example
{
    private int factor;
    public Example(int f)
    {
        factor = f;
    }

    public int SampleMethod(int x)
    {
        Console.WriteLine("\nExample.SampleMethod({0}) executes.", x);
        return x * factor;
    }

    public static void Main()
    {
        Assembly assem = typeof(Example).Assembly;

        Console.WriteLine("Assembly Full Name:");
        Console.WriteLine(assem.FullName);

        // The AssemblyName type can be used to parse the full name.
        AssemblyName assemName = assem.GetName();
        Console.WriteLine("\nName: {0}", assemName.Name);
        Console.WriteLine("Version: {0}.{1}",
            assemName.Version.Major, assemName.Version.Minor);

        Console.WriteLine("\nAssembly CodeBase:");
        Console.WriteLine(assem.CodeBase);

        // Create an object from the assembly, passing in the correct number
        // and type of arguments for the constructor.
        Object o = assem.CreateInstance("Example", false,
            BindingFlags.ExactBinding,
            null, new Object[] { 2 }, null, null);

        // Make a late-bound call to an instance method of the object.
        MethodInfo m = assem.GetType("Example").GetMethod("SampleMethod");
        Object ret = m.Invoke(o, new Object[] { 42 });
        Console.WriteLine("SampleMethod returned {0}.", ret);

        Console.WriteLine("\nAssembly entry point:");
        Console.WriteLine(assem.EntryPoint);
    }
}

/* This code example produces output similar to the following:

Assembly Full Name:
source, Version=1.0.2000.0, Culture=neutral, PublicKeyToken=null

Name: source
Version: 1.0

Assembly CodeBase:
file:///C:/sdtree/AssemblyClass/cs/source.exe

Example.SampleMethod(42) executes.
SampleMethod returned 84.

Assembly entry point:
Void Main()
 */

Imports System.Reflection
Imports System.Security.Permissions

<assembly: AssemblyVersionAttribute("1.0.2000.0")>

Public Class Example
    Private factor As Integer
    
    Public Sub New(ByVal f As Integer) 
        factor = f
    End Sub 
    
    Public Function SampleMethod(ByVal x As Integer) As Integer 
        Console.WriteLine(vbCrLf & "Example.SampleMethod({0}) executes.", x)
        Return x * factor
    End Function 
    
    Public Shared Sub Main() 
        Dim assem As Assembly = GetType(Example).Assembly
        
        Console.WriteLine("Assembly Full Name:")
        Console.WriteLine(assem.FullName)
        
        ' The AssemblyName type can be used to parse the full name.
        Dim assemName As AssemblyName = assem.GetName()
        Console.WriteLine(vbLf + "Name: {0}", assemName.Name)
        Console.WriteLine("Version: {0}.{1}", assemName.Version.Major, _
            assemName.Version.Minor)
        
        Console.WriteLine(vbLf + "Assembly CodeBase:")
        Console.WriteLine(assem.CodeBase)
        
        ' Create an object from the assembly, passing in the correct number
        ' and type of arguments for the constructor.
        Dim o As Object = assem.CreateInstance("Example", False, _
            BindingFlags.ExactBinding, Nothing, _
            New Object() { 2 }, Nothing, Nothing)
        
        ' Make a late-bound call to an instance method of the object.    
        Dim m As MethodInfo = assem.GetType("Example").GetMethod("SampleMethod")
        Dim ret As Object = m.Invoke(o, New Object() { 42 })
        Console.WriteLine("SampleMethod returned {0}.", ret)
        
        Console.WriteLine(vbCrLf & "Assembly entry point:")
        Console.WriteLine(assem.EntryPoint)
    
    End Sub 
End Class 

' This code example produces output similar to the following:
'
'Assembly Full Name:
'source, Version=1.0.2000.0, Culture=neutral, PublicKeyToken=null
'
'Name: source
'Version: 1.0
'
'Assembly CodeBase:
'file:///C:/sdtree/AssemblyClass/vb/source.exe
'
'Example.SampleMethod(42) executes.
'SampleMethod returned 84.
'
'Assembly entry point:
'Void Main()
'

Remarks

Use the Assembly class to load assemblies, to explore the metadata and constituent parts of assemblies, to discover the types contained in assemblies, and to create instances of those types.

To get an array of Assembly objects representing the assemblies currently loaded into an application domain (for example, the default application domain of a simple project), use the AppDomain.GetAssemblies method.

To load assemblies dynamically, the Assembly class provides the following static methods (Shared methods in Visual Basic). Assemblies are loaded into the application domain where the load operation occurs.

• The recommended way to load assemblies is to use the Load method, which identifies the assembly to be loaded by its display name (for example, "System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"). The search for the assembly follows the rules described in How the Runtime Locates Assemblies.

• The ReflectionOnlyLoad and ReflectionOnlyLoadFrom methods enable you to load an assembly for reflection, but not for execution. For example, an assembly that targets a 64-bit platform can be examined by code that is running on a 32-bit platform.

• The LoadFile and LoadFrom methods are provided for rare scenarios in which an assembly must be identified by path.

To get an Assembly object for the currently executing assembly, use the GetExecutingAssembly method.

Many members of the Assembly class provide information about an assembly. For example:

• The GetName method returns an AssemblyName object that provides access to the parts of the assembly display name.

• The GetCustomAttributes method lists the attributes applied to the assembly.

• The GetFiles method provides access to the files in the assembly manifest.

• The GetManifestResourceNames method provides the names of the resources in the assembly manifest.

The GetTypes method lists all the types in the assembly. The GetExportedTypes method lists the types that are visible to callers outside the assembly. The GetType method can be used to search for a particular type in the assembly. The CreateInstance method can be used to search for and create instances of types in the assembly.

For more information on assemblies, see the "Application Domains and Assemblies" section in the Application Domains topic.

Constructors

Assembly()

Initializes a new instance of the Assembly class.

Properties

CodeBase	Obsolete. Gets the location of the assembly as specified originally, for example, in an AssemblyName object.
CustomAttributes	Gets a collection that contains this assembly's custom attributes.
DefinedTypes	Gets a collection of the types defined in this assembly.
EntryPoint	Gets the entry point of this assembly.
EscapedCodeBase	Obsolete. Gets the URI, including escape characters, that represents the codebase.
ExportedTypes	Gets a collection of the public types defined in this assembly that are visible outside the assembly.
FullName	Gets the display name of the assembly.
GlobalAssemblyCache	Obsolete. Gets a value indicating whether the assembly was loaded from the global assembly cache (.NET Framework only).
HostContext	Gets the host context with which the assembly was loaded.
ImageRuntimeVersion	Gets a string representing the version of the common language runtime (CLR) saved in the file containing the manifest.
IsCollectible	Gets a value that indicates whether this assembly is held in a collectible AssemblyLoadContext.
IsDynamic	Gets a value that indicates whether the current assembly was generated dynamically in the current process by using reflection emit.
IsFullyTrusted	Gets a value that indicates whether the current assembly is loaded with full trust.
Location	Gets the full path or UNC location of the loaded file that contains the manifest.
ManifestModule	Gets the module that contains the manifest for the current assembly.
Modules	Gets a collection that contains the modules in this assembly.
ReflectionOnly	Gets a Boolean value indicating whether this assembly was loaded into the reflection-only context.
SecurityRuleSet	Gets a value that indicates which set of security rules the common language runtime (CLR) enforces for this assembly.

Methods

CreateInstance(String)	Locates the specified type from this assembly and creates an instance of it using the system activator, using case-sensitive search.
CreateInstance(String, Boolean)	Locates the specified type from this assembly and creates an instance of it using the system activator, with optional case-sensitive search.
CreateInstance(String, Boolean, BindingFlags, Binder, Object[], CultureInfo, Object[])	Locates the specified type from this assembly and creates an instance of it using the system activator, with optional case-sensitive search and having the specified culture, arguments, and binding and activation attributes.
CreateQualifiedName(String, String)	Creates the name of a type qualified by the display name of its assembly.
Equals(Object)	Determines whether this assembly and the specified object are equal.
GetAssembly(Type)	Gets the currently loaded assembly in which the specified type is defined.
GetCallingAssembly()	Returns the Assembly of the method that invoked the currently executing method.
GetCustomAttributes(Boolean)	Gets all the custom attributes for this assembly.
GetCustomAttributes(Type, Boolean)	Gets the custom attributes for this assembly as specified by type.
GetCustomAttributesData()	Returns information about the attributes that have been applied to the current Assembly, expressed as CustomAttributeData objects.
GetEntryAssembly()	Gets the entry assembly for the running application.
GetExecutingAssembly()	Gets the assembly that contains the code that is currently executing.
GetExportedTypes()	Gets the public types defined in this assembly that are visible outside the assembly.
GetFile(String)	Gets a FileStream for the specified file in the file table of the manifest of this assembly.
GetFiles()	Gets the files in the file table of an assembly manifest.
GetFiles(Boolean)	Gets the files in the file table of an assembly manifest, specifying whether to include resource modules.
GetForwardedTypes()
GetHashCode()	Returns the hash code for this instance.
GetLoadedModules()	Gets all the loaded modules that are part of this assembly.
GetLoadedModules(Boolean)	Gets all the loaded modules that are part of this assembly, specifying whether to include resource modules.
GetManifestResourceInfo(String)	Returns information about how the given resource has been persisted.
GetManifestResourceNames()	Returns the names of all the resources in this assembly.
GetManifestResourceStream(String)	Loads the specified manifest resource from this assembly.
GetManifestResourceStream(Type, String)	Loads the specified manifest resource, scoped by the namespace of the specified type, from this assembly.
GetModule(String)	Gets the specified module in this assembly.
GetModules()	Gets all the modules that are part of this assembly.
GetModules(Boolean)	Gets all the modules that are part of this assembly, specifying whether to include resource modules.
GetName()	Gets an AssemblyName for this assembly.
GetName(Boolean)	Gets an AssemblyName for this assembly, setting the codebase as specified by copiedName.
GetObjectData(SerializationInfo, StreamingContext)	Obsolete. Gets serialization information with all of the data needed to reinstantiate this assembly.
GetReferencedAssemblies()	Gets the AssemblyName objects for all the assemblies referenced by this assembly.
GetSatelliteAssembly(CultureInfo)	Gets the satellite assembly for the specified culture.
GetSatelliteAssembly(CultureInfo, Version)	Gets the specified version of the satellite assembly for the specified culture.
GetType()	Gets the Type of the current instance. (Inherited from Object)
GetType(String)	Gets the Type object with the specified name in the assembly instance.
GetType(String, Boolean)	Gets the Type object with the specified name in the assembly instance and optionally throws an exception if the type is not found.
GetType(String, Boolean, Boolean)	Gets the Type object with the specified name in the assembly instance, with the options of ignoring the case, and of throwing an exception if the type is not found.
GetTypes()	Gets all types defined in this assembly.
IsDefined(Type, Boolean)	Indicates whether or not a specified attribute has been applied to the assembly.
Load(AssemblyName)	Loads an assembly given its AssemblyName.
Load(Byte[])	Loads the assembly with a common object file format (COFF)-based image containing an emitted assembly.
Load(Byte[], Byte[])	Loads the assembly with a common object file format (COFF)-based image containing an emitted assembly, optionally including symbols for the assembly.
Load(String)	Loads an assembly with the specified name.
LoadFile(String)	Loads the contents of an assembly file on the specified path.
LoadFrom(String)	Loads an assembly given its file name or path.
LoadFrom(String, Byte[], AssemblyHashAlgorithm)	Loads an assembly given its file name or path, hash value, and hash algorithm.
LoadModule(String, Byte[])	Loads the module, internal to this assembly, with a common object file format (COFF)-based image containing an emitted module, or a resource file.
LoadModule(String, Byte[], Byte[])	Loads the module, internal to this assembly, with a common object file format (COFF)-based image containing an emitted module, or a resource file. The raw bytes representing the symbols for the module are also loaded.
LoadWithPartialName(String)	Obsolete. Loads an assembly from the application directory or from the global assembly cache using a partial name.
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ReflectionOnlyLoad(Byte[])	Obsolete. Loads the assembly from a common object file format (COFF)-based image containing an emitted assembly. The assembly is loaded into the reflection-only context of the caller's application domain.
ReflectionOnlyLoad(String)	Obsolete. Loads an assembly into the reflection-only context, given its display name.
ReflectionOnlyLoadFrom(String)	Obsolete. Loads an assembly into the reflection-only context, given its path.
ToString()	Returns the full name of the assembly, also known as the display name.
UnsafeLoadFrom(String)	Loads an assembly into the load-from context, bypassing some security checks.

Operators

Equality(Assembly, Assembly)	Indicates whether two Assembly objects are equal.
Inequality(Assembly, Assembly)	Indicates whether two Assembly objects are not equal.

Events

ModuleResolve

Occurs when the common language runtime class loader cannot resolve a reference to an internal module of an assembly through normal means.

Extension Methods

GetExportedTypes(Assembly)
GetModules(Assembly)
GetTypes(Assembly)
GetCustomAttribute(Assembly, Type)	Retrieves a custom attribute of a specified type that is applied to a specified assembly.
GetCustomAttribute<T>(Assembly)	Retrieves a custom attribute of a specified type that is applied to a specified assembly.
GetCustomAttributes(Assembly)	Retrieves a collection of custom attributes that are applied to a specified assembly.
GetCustomAttributes(Assembly, Type)	Retrieves a collection of custom attributes of a specified type that are applied to a specified assembly.
GetCustomAttributes<T>(Assembly)	Retrieves a collection of custom attributes of a specified type that are applied to a specified assembly.
IsDefined(Assembly, Type)	Indicates whether custom attributes of a specified type are applied to a specified assembly.
TryGetRawMetadata(Assembly, Byte*, Int32)	Retrieves the metadata section of the assembly, for use with MetadataReader.

Thread Safety

This type is thread safe.

See also

• AppDomain
• AssemblyName
• Application Domains