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OpCodes.Ldelema Field

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Loads the address of the array element at a specified array index onto the top of the evaluation stack as type & (managed pointer).

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

Syntax

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

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

8F < T >

ldelema class

Loads the address of the array element at index onto the top of the evaluation stack as type & (managed pointer).

The stack transitional behavior, in sequential order, is:

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

  2. An index value index is pushed onto the stack.

  3. index and array are popped from the stack; the address stored at position index in array is looked up.

  4. The address is pushed onto the stack.

The ldelema is used to retrieve the address of an object at a particular index in an array of objects (of type class). The ldelema instruction loads the address of the value at index index (type native int) in the zero-based one-dimensional array array and places it on the top of the stack. Arrays are objects and hence represented by a value of type O. The value must be of type class passed with the instruction.

The return value for ldelema is a managed pointer (type &).

Note that integer values of less than 4 bytes are extended to int32 (not native int) when they are loaded onto the evaluation stack.

NullReferenceException is thrown if array is a null reference.

ArrayTypeMismatchException is thrown if array does not hold elements of the required type.

IndexOutOfRangeException is thrown if index is negative, or larger than the bound of array.

The following Emit method overload can use the ldelema opcode:

  • ILGenerator.Emit(OpCode, Type)

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.