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OpCodes.Dup Field

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Copies the current topmost value on the evaluation stack, and then pushes the copy onto the evaluation stack.

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

Syntax

'Declaration
Public Shared ReadOnly Dup As OpCode
public static readonly OpCode Dup

Remarks

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

25

dup

Duplicates the value on the top of the stack.

The stack transitional behavior, in sequential order, is:

  1. value is pushed onto the stack.

  2. value is popped off of the stack for duplication.

  3. value is pushed back onto the stack.

  4. A duplicate value is pushed onto the stack.

The dup instruction duplicates the top element of the stack, and leaves two identical values atop it.

The following Emit method overload can use the dup opcode:

  • ILGenerator.Emit(OpCode)

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.