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Declare Sub sx_CreateField Lib "Apollo9.dll"
(ByVal cpFldName As String,
ByVal cpFldType As String,
ByVal iFldLen As Integer,
ByVal iFldDec As Integer)
VOID FAR PASCAL sx_CreateField
(BYTEP cpFldName,
BYTEP cpFldType,
SHORT iFldLen,
SHORT iFldDec);
Defines a field to be included in a new table. A new file is created by first making a work area with sx_CreateNew (which also defines the number of fields that the table will contain). Each field is then defined with sx_CreateField, and the file is finally physically created by calling sx_CreateExec.
The number of calls to sx_CreateField must not exceed the defined number of fields passed as parameter iNumFields to function sx_CreateNew.
cpFldName: The name of the field. Valid field names begin with a letter and may contain letters, numbers, and the underscore character. Field name maximum length is ten characters.
cpFldType: The xBase drivers allow the following types:
C for Character
N for Numeric
D for Date
F for Float
I for Integer (strongly-typed VariField)
L for Logical
M for Memo
V for VariField
iFldLen: Field length. The maximum lengths for various types are:
C 32733 (32k - 34)
N 19
D 3 (VariField DATE)
D 8 (CCYYMMDD)
I 4 (VariField Long Integer value, ±2 billion)
L 1
M 10 (default 10 to hold memo block reference)
V 6+ (weakly-typed value)
Field lengths for D, L, and M types are automatically set to 8, 1, and 10 respectively.
The maximum length of a character field that can be extracted with the sx_Get* functions is 1023. Larger fields must be extracted with sx_GetRecord. Memo and weakly-typed VariField must be extracted with sx_GetMemo.
iFldDec: The number of decimal positions if the field type is numeric. Note that the length of a numeric field that contains decimals includes the decimal point, a leading zero, and an optional sign. The minimum length for a numeric field that contains one decimal position is therefore 3 (unsigned) or 4 (signed). The maximum number of decimals allowed in DBF files is 16.
Sub ButtonMake_Click ()
iRet = sx_CreateNew("c:\data\testnew.dbf", "test", SDEFOX, 5)
If iRet = 0 Then
MsgBox "create failed"
Else
sx_CreateField "fchar", "C", 25, 0
sx_CreateField "fnum", "N", 10, 2
sx_CreateField "flog", "L", 1, 0
sx_CreateField "fdate", "D", 8, 0
sx_CreateField "fmemo", "M", 10, 0
If sx_CreateExec() Then
MsgBox "Create succeeded"
sx_Close
Else
MsgBox "create failed"
End If
End If
End Sub
void CNamesForm::OnInitialUpdate()
{
// do default func first
CFormView::OnInitialUpdate();
// enable float support for VBXs
CVBControl::EnableVBXFloat();
// check if database exists
// and, if not, create
CFileStatus status;
char* pFileName = "names.dbf";
// if CFile status FALSE, create new file
if (!CFile::GetStatus(pFileName, status))
{
sx_CreateNew((BYTEP) "names.dbf", (BYTEP) "name", SDENTX, 5);
sx_CreateField((BYTEP) "name", (BYTEP) "C", 30, 0);
sx_CreateField((BYTEP) "address", (BYTEP) "C", 30, 0);
sx_CreateField((BYTEP) "phone", (BYTEP) "C", 10, 0);
sx_CreateField((BYTEP) "business", (BYTEP) "C", 20, 0);
sx_CreateField((BYTEP) "createdate", (BYTEP) "D", 8, 0);
sx_CreateExec();
sx_Close();
}
}