OpCodes.Cpblk Field

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Copies a specified number bytes from a source address to a destination address.

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

Syntax

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

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

FE 17

cpblk

Copy data from one memory block to another.

The stack transitional behavior, in sequential order, is:

  1. The destination address is pushed onto the stack.

  2. The source address is pushed onto the stack.

  3. The number of bytes to copy is pushed onto the stack.

  4. The number of bytes, the source address, and the destination address are popped from the stack; the specified number of bytes are copied from the source address to the destination address.

The cpblk instruction copies a number (type unsigned int32) of bytes from a source address (of type *, native int, or &) to a destination address (of type *, native int, or &). The behavior of cpblk is unspecified if the source and destination areas overlap.

cpblk assumes that both the source and destination addressed are aligned to the natural size of the machine. The cpblk instruction can be immediately preceded by the unaligned.<prefix> instruction to indicate that either the source or the destination is unaligned.

The operation of the cpblk instruction can be altered by an immediately preceding Volatile or Unaligned prefix instruction.

NullReferenceException may be thrown if an invalid address is detected.

The following Emit method overload can use the cpblk 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.