DFX_Byte

Transfers single bytes between the field data members of a CDaoRecordset object and the columns of a record on the data source.

void AFXAPI DFX_Byte(
   CDaoFieldExchange* pFX,
   LPCTSTR szName,
   BYTE& value,
   DWORD dwBindOptions = AFX_DAO_ENABLE_FIELD_CACHE 
);

Parameters

pFX
A pointer to an object of class CDaoFieldExchange. This object contains information to define the context for each call of the function.
szName
The name of a data column.
value
The value stored in the indicated data member — the value to be transferred. For a transfer from recordset to data source, the value, of type BYTE, is taken from the specified data member. For a transfer from data source to recordset, the value is stored in the specified data member.
dwBindOptions
An option that lets you take advantage of MFC's double buffering mechanism for detecting recordset fields that have changed. The default, AFX_DAO_ENABLE_FIELD_CACHE, uses double buffering. The other possible value is AFX_DAO_DISABLE_FIELD_CACHE. If you specify this value, MFC does no checking on this field. You must call SetFieldDirty and SetFieldNull yourself.

注意

You can control whether data is double buffered by default by setting CDaoRecordset::m_bCheckCacheForDirtyFields.

Data is mapped between type DAO_BYTES in DAO and type BYTE in the recordset.

Header: afxdao.h