CDaoFieldExchange::IsValidOperation

If you write your own DFX function, call IsValidOperation at the beginning of your function to determine whether the current operation can be performed on a particular field data member type (a CDaoFieldExchange::outputColumn or a CDaoFieldExchange::param).

BOOL IsValidOperation( );

Return Value

Nonzero if the current operation is appropriate for the type of field being updated.

Remarks

Some of the operations performed by the DFX mechanism apply only to one of the possible field types. Follow the model of the existing DFX functions.

For additional information on writing custom DFX routines, see Technical Note 53.

Requirements

Header: afxdao.h

See Also

Reference

CDaoFieldExchange Class

Hierarchy Chart

CDaoFieldExchange::SetFieldType