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IMetaDataEmit::SetClassLayout Method

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Completes the layout of fields for a class that has been defined by a prior call to DefineTypeDef Method.

Syntax

HRESULT SetClassLayout (  
    [in]  mdTypeDef           td,
    [in]  DWORD               dwPackSize,
    [in]  COR_FIELD_OFFSET    rFieldOffsets[],
    [in]  ULONG               ulClassSize
);

Parameters

td
[in] An mdTypeDef token that specifies the class to be laid out.

dwPackSize
[in] The packing size: 1, 2, 4, 8 or 16 bytes. The packing size is the number of bytes between adjacent fields.

rFieldOffsets
[in] An array of COR_FIELD_OFFSET structures, each of which specifies a field of the class and the field's offset within the class. Terminate the array with mdTokenNil.

ulClassSize
[in] The size, in bytes, of the class.

Remarks

The class is initially defined by calling the IMetaDataEmit::DefineTypeDef method, and specifying one of three layouts for the fields of the class: automatic, sequential, or explicit. Normally, you would use automatic layout and let the runtime choose the best way to lay out the fields.

However, you might want the fields laid out according to the arrangement that unmanaged code uses. In this case, choose either sequential or explicit layout and call SetClassLayout to complete the layout of the fields:

  • Sequential layout: Specify the packing size. A field is aligned according to either its natural size or the packing size, whichever results in the smaller offset of the field. Set rFieldOffsets and ulClassSize to zero.

  • Explicit layout: Either specify the offset of each field or specify the class size and the packing size.

Requirements

Platforms: See System Requirements.

Header: Cor.h

Library: Used as a resource in MSCorEE.dll

.NET Framework Versions: Available since 1.0

See also