Load Method (String)

Assembly::Load Method (String^)


Loads an assembly given the long form of its name.

Namespace:   System.Reflection
Assembly:  mscorlib (in mscorlib.dll)

static Assembly^ Load(
	String^ assemblyString


Type: System::String^

The long form of the assembly name.

Return Value

Type: System.Reflection::Assembly^

The loaded assembly.

Exception Condition

assemblyString is null.


assemblyString is a zero-length string.


assemblyString is not found.


A file that was found could not be loaded.


assemblyString is not a valid assembly.


Version 2.0 or later of the common language runtime is currently loaded and assemblyString was compiled with a later version.

The long form of an assembly name consists of its simple name (such as "System" for the System.dll assembly) along with its version, culture, public key token, and optionally its processor architecture. It corresponds to the assembly's FullName property. The following example illustrates the use of a long name to load the System.dll assembly for the .NET Framework 4.

No code example is currently available or this language may not be supported.

FileLoadException is thrown if assemblyString specifies the full assembly name, and the first assembly that matches the simple name has a different version, culture, or public key token. The loader does not continue probing for other assemblies that match the simple name.

Whether certain permissions are granted or not granted to an assembly is based on evidence. The rules for assembly and security evidence merging are as follows:

  • When you use a Load method with no Evidence parameter, the assembly is loaded with the evidence that the loader supplies.

  • When you use a Load method with an Evidence parameter, pieces of evidence are merged. Pieces of evidence supplied as an argument to the Load method supersede pieces of evidence supplied by the loader.

  • When you use a Load method overload with a Byte[] parameter to load a common object file format (COFF) image, evidence is inherited from the calling assembly. This applies to the .NET Framework version 1.1 Service Pack 1 (SP1) and subsequent releases.


    In the .NET Framework version 1.0 and in version 1.1 without SP1, when you use a Load method overload with a Byte[] parameter to load a COFF image, evidence is combined. Zone, Url and Site are inherited from the calling assembly, and Hash and StrongName are taken from the COFF assembly.

  • When you use a Load method with a Byte[] parameter and Evidence to load a COFF image, only the supplied evidence is used. Evidence of the calling assembly and evidence of the COFF image is ignored.

Reflecting on C++ executable files might throw a BadImageFormatException. This is most likely caused by the C++ compiler stripping the relocation addresses or the .reloc section from your executable file. To preserve the .reloc address for your C++ executable file, specify /fixed:no when you are linking.

In the .NET Framework version 2.0, processor architecture is added to assembly identity, and can be specified as part of assembly name strings. For example, "ProcessorArchitecture=msil". However, the recommended way to specify an assembly name is to create an AssemblyName object and pass it to an appropriate overload of the Load method. See AssemblyName::ProcessorArchitecture.

The following example loads an assembly given its fully qualified name, and lists all the types contained in the specified assembly. For this code example to run, you must provide the fully qualified assembly name. For information about how to obtain the fully qualified assembly name, see Assembly Names.

using namespace System;
using namespace System::Collections;
using namespace System::Reflection;
int main()
    // You must supply a valid fully qualified assembly name.            
    Assembly^ SampleAssembly = Assembly::Load
        ( "SampleAssembly, Version=1.0.2004.0, Culture=neutral, PublicKeyToken=8744b20f8da049e3" );
    array<Type^>^ Types = SampleAssembly->GetTypes();

    // Display all the types contained in the specified assembly.
    IEnumerator^ myEnum = Types->GetEnumerator();
    Type^ oType;
    while ( myEnum->MoveNext() )
        oType = safe_cast<Type^>(myEnum->Current);
        Console::WriteLine( oType->Name );


to load an assembly with evidence. Associated enumeration: SecurityPermissionFlag::ControlEvidence

.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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