void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, BYTE& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, int& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, UINT& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, long& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, DWORD& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, CString& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, float& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, double& value, CRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, short& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, BOOL& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, BYTE& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, long& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, DWORD& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, CString& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, float& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, double& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, COleDateTime& value, CDaoRecordset* pRecordset );
void AFXAPI DDX_FieldText( CDataExchange* pDX, int nIDC, COleCurrency& value, CDaoRecordset* pRecordset );
Parameters
pDX
A pointer to a CDataExchange object. The framework supplies this object to establish the context of the data exchange, including its direction.
nIDC
The ID of a control in the CRecordView or CDaoRecordView object.
value
A reference to a field data member in the associated CRecordset or CDaoRecordset object. The data type of value depends on which of the overloaded versions of DDX_FieldText you use.
pRecordset
A pointer to the CRecordset or CDaoRecordset object with which data is exchanged. This pointer enables DDX_FieldText to detect and set Null values.
Remarks
The DDX_FieldText function manages the transfer of int, short, long, DWORD, CString, float, double, BOOL, or BYTE data between an edit box control and the field data members of a recordset. For CDaoRecordset objects, DDX_FieldText also manages transferring COleDateTime, and COleCurrency values. An empty edit box control indicates a Null value. On a transfer from the recordset to the control, if the recordset field is Null, the edit box is set to empty. On a transfer from control to recordset, if the control is empty, the recordset field is set to Null.
Use the versions with CRecordset parameters if you are working with the ODBC-based classes. Use the versions with CDaoRecordset parameters if you are working with the DAO-based classes.
For more information about DDX, see Adding a Dialog Box in Visual C++ Tutorials and Dialog Data Exchange and Validation in Visual C++ Programmer’s Guide. For examples and more information about DDX for CRecordView and CDaoRecordView fields, see the article Record Views in Visual C++ Programmer’s Guide.
Example
The following DoDataExchange function for a CRecordView contains DDX_FieldText function calls for three data types: IDC_COURSELIST
is a combo box; the other two controls are edit boxes. For DAO programming, the m_pSet parameter is a pointer to a CRecordset or CDaoRecordset.
//Example for DDX_FieldText
void CSectionForm::DoDataExchange( CDataExchange* pDX )
{
CRecordView::DoDataExchange( pDX );
//{{AFX_DATA_MAP(CSectionForm)
DDX_FieldCBString( pDX, IDC_COURSELIST,
m_pSet->m_strCourseID, m_pSet);
DDX_FieldText( pDX, IDC_ROOM, m_pSet->m_nRoomNo,
m_pSet );
DDX_FieldText( pDX, IDC_TUITION,
m_pSet->m_dwTuition, m_pSet );
//}}AFX_DATA_MAP
}
See Also DDX_FieldRadio, DDX_FieldLBString, DDX_FieldLBStringExact, DDX_FieldCBString, DDX_FieldCBStringExact, DDX_FieldCBIndex, DDX_FieldLBIndex, DDX_FieldScroll