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OpCodes.Unbox_Any Field

Converts the boxed representation of a type specified in the instruction to its unboxed form.

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

public static readonly OpCode Unbox_Any

The following table lists the instruction's hexadecimal and Microsoft intermediate language (MSIL) assembly format, along with a brief reference summary:

Format

Assembly Format

Description

A5 < T >

unbox.any typeTok

Extract the data from obj, its boxed representation.

The stack transitional behavior, in sequential order, is:

  1. An object reference obj is pushed onto the stack.

  2. The object reference is popped from the stack and unboxed to the type specified in the instruction.

  3. The resulting object reference or value type is pushed onto the stack.

When applied to the boxed form of a value type, the unbox.any instruction extracts the value contained within obj (of type O), and is therefore equivalent to unbox followed by ldobj.

When applied to a reference type, the unbox.any instruction has the same effect as castclass  typeTok.

If the operand typeTok is a generic type parameter, then the runtime behavior is determined by the type that is specified for that generic type parameter.

InvalidCastException is thrown if obj is not a boxed type.

NullReferenceException is thrown if obj is a null reference.

The following Emit method overload can use the unbox.any opcode:

  • ILGenerator.Emit(OpCode, Type)

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0
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