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const
//====================================================================
FieldPropType_Required = $01;
FieldPropType_Min = $02;
FieldPropType_Max = $03;
FieldPropType_Default = $04;
FieldPropType_Constraint = $06;
FieldDescVII_AutoIncOffset = 42;
//====================================================================
// File structures
//====================================================================
type
PDbfHdr = ^rDbfHdr;
rDbfHdr = packed record
VerDBF : Byte; // 0
Year : Byte; // 1 year last updated
Month : Byte; // 2 month last updated
Day : Byte; // 3 day last updated
RecordCount : Integer; // 4-7 number of records in file
FullHdrSize : Word; // 8-9
RecordSize : Word; // 10-11 sum of all field sizes, including delete flag
Dummy1 : Word; // 12-13
IncTrans : Byte; // 14
Encrypt : Byte; // 15 DBase encryption flag
MultiUse : Integer; // 16-19
LastUserID : Integer; // 20-23
Dummy2 : array[24..27] of Byte;
// $01: mdx (or cdx for VFP) index file present
// $02: (Visual FoxPro): associated memo file?
// $04: (Visual FoxPro): is this a dbc/database container
MDXFlag : Byte; // 28 Flags:
Language : Byte; // 29 code page mark
Dummy3 : Word; // 30-31
end;
//====================================================================
PAfterHdrIII = ^rAfterHdrIII;
rAfterHdrIII = packed record // Empty
end;
//====================================================================
PAfterHdrVII = ^rAfterHdrVII;
rAfterHdrVII = packed record
LanguageDriverName : array[32..63] of Char;
Dummy : array[64..67] of Byte;
end;
//====================================================================
// DBase III,IV,FoxPro,VisualFoxPro field description
PFieldDescIII = ^rFieldDescIII;
rFieldDescIII = packed record
FieldName : array[0..10] of Char;
FieldType : Char; // 11
// FieldOffset: (V)FoxPro only: displacement of field in record
// DBase III uses it for address in memory
FieldOffset : Integer; // 12..15
FieldSize : Byte; // 16
FieldPrecision : Byte; // 17, also known as decimal count
// $01: system solumn (not user-visible)
// $02: column can store null values
// $04: binary column, e.g. don't interpret codepage (char/memo fields)
// $0C: column is autoincrementing (only integer fields)
VisualFoxProFlags : Byte; // 18 Field Flags; flags can be combined
// (!!not the next value for a new record!!); the next is calculated by
// adding AutoIncrementStep first.
// Value covers bytes 19..22 (so no WorkAreaID,Reserved1 for VFP)
AutoIncrementNext : Byte; // 19 VFP only: autoincrement value
// WorkAreaID only for DBase III, is always $01
WorkAreaID : Byte; // 20
Reserved1 : array[21..22] of Byte;
AutoIncrementStep : Byte; // 23 VFP only: step value for autoincrement
Reserved2 : array[24..30] of Byte;
// DBase IV:
// $00: no key for this field;
// $01: key exists for this field in MDX index file
// todo: implement this??
MDXIndexField : Byte; //31
end;
//====================================================================
// OH 2000-11-15 dBase7 support. Header Update (add fields like Next AutoInc Value)
rFieldDescVII = packed record
FieldName : array [0..31] of Char;
FieldType : Char; // 32
FieldSize : Byte; // 33
FieldPrecision : Byte; // 34
Reserved1 : Word; // 35-36
MDXFlag : Byte; // 37
// NOTE: the docs say Reserved2 is 2 bytes, and Reserved3 is 4 bytes
// but testing shows BDE has them the other way around
// be BDE compatible :S
Reserved2 : Cardinal; // 38-41
NextAutoInc : Cardinal; // 42-45
Reserved3 : Word; // 46-47
end;
//====================================================================
PFieldPropsHdr = ^rFieldPropsHdr;
rFieldPropsHdr = packed record
NumStdProps : Word; // 0..1
StartStdProps : Word; // 2..3
NumCustomProps : Word; // 4..5
StartCustomProps : Word; // 6..7
NumRIProps : Word; // 8..9
StartRIProps : Word; // 10..11
StartData : Word; // 12..13 ; this points past the Descriptor arrays to data used by the arrays - for example Custom property names are stored here.
Size : Word; // 14..15 ; Actual size of structure, including data
end;
//====================================================================
PStdPropEntry = ^rStdPropEntry;
rStdPropEntry = packed record
GenNumber : Word; // 0..1 ; Generational number. More than one value may exist for a property. The current value is the value with the highest generational number.
FieldOffset : Word; // 2..3 ; Table field offset - base one. 01 for the first field in the table, 02 for the second field, etc. Note: this will be 0 in the case of a constraint.
PropType : Byte; // 4 ; Which property is described in this record:
// 01 Required
// 02 Min
// 03 Max
// 04 Default
// 06 Database constraint
FieldType : Byte; // 5 ; Field Type:
// 00 No type - constraint
// 01 Char
// 02 Numeric
// 03 Memo
// 04 Logical
// 05 Date
// 06 Float
// 08 OLE
// 09 Binary
// 11 Long
// 12 Timestamp
// 13 Double
// 14 AutoIncrement (not settable from the Inspector)
IsConstraint : Byte; // 6 ; 0x00 if the array element is a constraint, 0x02 otherwise.
Reserved : array[7..10] of Char;
DataOffset : Word; // 11..12 ; Offset from the start of this structure to the data for the property. The Required property has no data associated with it, so it is always 0.
DataSize : Word; // 13..14 ; Width of database field associated with the property, and hence size of the data (includes 0 terminator in the case of a constraint).
end;
//====================================================================
PCustomPropEntry = ^rCustomPropEntry;
rCustomPropEntry = packed record
GenNumber : Word; // 0..1 ; same as standard
FieldOffset : Word; // 2..3 ; same as standard
FieldType : Byte; // 4 ; same as standard
Reserved : Byte; // 5
NameOffset : Word; // 6..7 ; Offset from the start of this structure to the Custom property name.
NameLength : Word; // 8..9 ; Length of the Custom property name.
DataOffset : Word; // 10..11 ; Offset from the start of this structure to the Custom property data.
DataLength : Word; // 12..13 ; Length of the Custom property data (does not include null terminator).
end;
//====================================================================
PRIPropEntry = ^rRIPropEntry;
rRIPropEntry = packed record
RelationType : Byte; // 0 ; 0x07 if Master (parent), 0x08 if Dependent (child).
Number : Word; // 1..2 ; Sequential number, 1 based counting. If this number is 0, this RI rule has been dropped.
NameOffset : Word; // 3..4 ; Offset of the RI rule name - 0 terminated.
NameSize : Word; // 5..6 ; Size of ...
ForeignOffset : Word; // 7..8 ; Offset of the name of the Foreign Table - 0 terminated.
ForeignSize : Word; // 9..10 ; Size of ...
UpdateType : Byte; // 11 ; Update & delete behaviour: Update Cascade=0x10, Delete Cascade=0x01
NumFieldsKey : Word; // 12..13 ; Number of fields in the linking key.
LocalTagOffset : Word; // 14..15 ; Offset of the Local Table tag name - 0 terminated.
LocalTagSize : Word; // 16..17 ; Size of ...
ForeignTagOffset: Word; // 18..19 ; Offset of the Foreign Table tag name - 0 terminated.
ForeignTagSize : Word; // 20..21 ; Size of ...
end;
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