PFNDPAMERGECONST callback function (dpa_dsa.h)

Defines the prototype for the merge function used by DPA_Merge, using constant values.

Syntax

PFNDPAMERGECONST Pfndpamergeconst;

const void * Pfndpamergeconst(
  [in] UINT uMsg,
  [in] const void *pvDest,
  [in] const void *pvSrc,
  [in] LPARAM lParam
)
{...}

Parameters

[in] uMsg

Type: UINT

A message that instructs this function how to handle the merge. One of the following values.

Value Meaning
DPAMM_MERGE
0x1
Perform any additional processing needed when merging p2 into p1. The function should return a pointer to an item that contains the result of the merge.
DPAMM_DELETE
0x2
Perform any additional processing needed when a delete occurs as part of the merge. The function should return NULL.
DPAMM_INSERT
0x3
Perform any user-defined processing when the merge results in an item being inserted as part of the merge. The return value of this function should point to the item result that is inserted as part of the merge.

[in] pvDest

Type: const void*

A pointer to the destination item in the merge.

[in] pvSrc

Type: const void*

A pointer to the source item in the merge.

[in] lParam

Type: LPARAM

Additional data that can be used by the merge callback.

Return value

Type: const void*

A pointer to constant data which results from the merge, or NULL if there is a failure when DPAMM_MERGE or DPAMM_INSERT is used.

Requirements

   
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Target Platform Windows
Header dpa_dsa.h

See also

PFNDPAMERGE