Difference entre foxpro et visual foxpro

Question

>Bonjour à tous,
Voila deux ans que je travaille sur foxpro (tant bien que mal...) et j'apprend aujourd'hui qu'il est possible que la base ai été migré de foxpro vers visual foxpro et que cette manipulation n'aurait pas été faites sur les fichiers.

Quelqu'un pourrais t'il eclairé ma lanterne car j'ai du mal a comprendre. J'ai toujours pensé jusqu'a maintenant que les fichiers etaient les meme depuis le debut de foxpro.

Comment voir en quel version sont les fichiers ainsi que la base, et comment les faires migrer. 

Merci de votre aide.

duck88

Mike Gagnon · Answer

Voici un example comment determiner certaines informations sur un table Foxpro close all public filehandle, rdfile, ctype, nrecords, nposrec1, nreclen, nfldpos, cfield public cfldtype, nflddec, nfldlen, nfldcnt, lhasmem, lhascdx, lisdbc, lisbin public nfldflag, cassdbc, nfilesize, dtmp, nAutoIncrNextVal, nAutoIncrStepVal public cSetDate, cSetCentury, lcdxmemdbcError, nfilesizediff, lisvfp, nFldProblem dimension dbfhdr[32] cSetDate = SET('DATE') cSetCentury = SET('CENTURY') SET DATE YMD SET CENTURY off cfldtype='' nfldlen=0 nfldcnt=0 nfldflag=0 nfilesize=0 cassdbc='' rdfile=space(30) lcdxmemdbcError=.f. * get filename do getfname * read fileheader do readheader lisvfp = (dbfhdr[1]=48 or dbfhdr[1]=49) ctype = FileType(dbfhdr[1]) && determine the filetype nrecords=dbfhdr[5]+dbfhdr[6]*256+dbfhdr[7]*256^2+dbfhdr[8]*256^3 && calculate the number of records (bytes 5,6,7 and 8) nreclen=dbfhdr[11]+dbfhdr[12]*256 && calculete the record length (bytes 11 and 12) nposrec1=dbfhdr[9]+dbfhdr[10]*256 + 1 && calculate the position of the first record (bytes 9 and 10) dtmp=CTOD(tran(dbfhdr[2],'@L 99')+'/'+tran(dbfhdr[3],'@L 99')+'/'+tran(dbfhdr[4],'@L 99')) && check for a valid update date do cdxmemdbc && determine if this dbf has a structural index file and/or a memo file ? 'Headerinfo on '+rdfile ? ? 'Code / Type :',tran( dbfhdr[1],'@L 99')+' '+ctype ? 'Last update :',tran(dbfhdr[2],'@L 99')+' '+tran(dbfhdr[3],'@L 99')+' '+tran(dbfhdr[4],'@L 99') ? 'Number of records:',ltrim(str(nrecords)) ? 'Position 1st rec :',ltrim(str(nposrec1,5)) ? 'Header length :',ltrim(str(nposrec1-1,5)) ? 'Record length :',ltrim(str(nreclen,5)) ? 'File size :',ltrim(str(nfilesize,8)) ? 'Struct Index File:',iif(lcdxmemdbcError,'Unknown/Invalid code found',iif(lhascdx,'Yes','No')) ? 'Memo file ;',iif(lcdxmemdbcError,'Unknown/Invalid code found',iif(lhasmem,'Yes','No')) ? 'File is a VFP DBC:',iif(lcdxmemdbcError,'Unknown/Invalid code found',iif(lisdbc,'Yes','No')) ? 'Number of fields :',ltrim(str( iif(lisvfp,(nposrec1-296)/32, (nposrec1-33)/32) ) ) ? 'Codepage mark :',ltrim(str(dbfhdr[30]))+' (',ShowCodePageInfo(dbfhdr[30])+' )' nEnddef=0 nFldProblem=0 FOR x=64 TO nfilesize-1 step 32 =FSEEK(filehandle, x,0) nbyte= ASC(FREAD(filehandle,1)) IF nbyte= 13 && 0x0D nEnddef = x+1 EXIT ENDIF NEXT ? * read field definitions... * the field definitions start at byte 33 * so first move to that position * check filetype for different approach when it is a visual foxpro file do case case dbfhdr[1]=3 or dbfhdr[1]=131 or dbfhdr[1]=139 or dbfhdr[1]=245 && Not a VFP file =fseek(filehandle,32,0) && position at field def positions ? 'Structure of '+rdfile ***1234567890123456789012345678901234567890123456789 ? 'Field/name type length offset' ? ' in rec' ? '---------------------------------' do while fseek(filehandle,0,1) < nposrec1-32 nfldcnt=nfldcnt+1 cfield=fread(filehandle,11) cfield=STRTRAN(cfield,CHR(0),' ') cfldtype=fread(filehandle,1) nfldpos=asc(fread(filehandle,1)) =fseek(filehandle,3,1) nfldlen=asc(fread(filehandle,1)) * if the field is type N find out how many decimals there are if cfldtype='N' nflddec=asc(fread(filehandle,1)) =fseek(filehandle,14,1) else =fseek(filehandle,15,1) endif ? tran(nfldcnt,'@L 999'),padr(cfield,11), cfldtype,str(nfldlen,5)+iif(cfldtype='N','.'+ltrim(str(nflddec)),' '),str(nfldpos,5) * test field length specificatons DO CASE CASE cfldtype='D' && this field should have a length of 8 bytes IF nfldlen<>8 ?? ' Invalid fieldlength, length should be 8' nFldProblem=nFldProblem+1 ENDIF CASE cfldtype$'GIPTY' && these fields are invalid for non visual foxpro dbfs ?? 'Invalid fieldtype' nFldProblem=nFldProblem+1 CASE cfldtype='C' && this field should have a length of 1-254 bytes IF !BETWEEN(nfldlen,1,254) ?? ' Invalid fieldlength, length should be 1-254' nFldProblem=nFldProblem+1 ENDIF CASE cfldtype$'NF' && these fields all should have a length of 1-20 bytes IF !BETWEEN(nfldlen,1,20) ?? ' Invalid fieldlength, length should be 1-20' nFldProblem=nFldProblem+1 IF nflddec> 18 && field decimals must be fieldlen - 2 maximal nFldProblem=nFldProblem+1 ?? ' Invalid number of decimals, max value is 18' ENDIF ELSE && field length in normal range, check number of decimals IF nflddec>0 && field decimals defined and fieldlen OK IF nfldlen - nflddec< 2 && field decimals must be fieldlen - 2 maximal ?? ' Invalid number of decimals, max value is '+LTRIM(STR(nfldlen - 2)) nFldProblem=nFldProblem+1 ENDIF ENDIF ENDIF CASE cfldtype='L' && this field should have a length of 1 byte IF nfldlen<>1 ?? ' Invalid fieldlength, length should be 1' nFldProblem=nFldProblem+1 ENDIF CASE cfldtype='M' && this field should have a length of 4 bytes IF nfldlen<>4 ?? ' Invalid fieldlength, length should be 4' nFldProblem=nFldProblem+1 ENDIF ENDCASE enddo ? '---------------------------------' case lisvfp && visual foxpro file =fseek(filehandle,32,0) && position at field def positions ? 'Structure of '+rdfile ***1234567890123456789012345678901234567890123456789 ? 'Field/name type length offset fieldflag AutoIncr AutoIncr ' ? ' in rec NextValue StepValue' ? '----------------------------------------------------------------------' do while fseek(filehandle,0,1) < nposrec1-(295) nAutoIncrNextVal = 0 nAutoIncrStepVal = 0 nfldcnt=nfldcnt+1 cfield=fread(filehandle,11) && first 11 bytes cfldtype=fread(filehandle,1) && byte 12 * bytes 13, 14, 15 and 16 nfldpos=asc(fread(filehandle,1))+asc(fread(filehandle,1))*256+asc(fread(filehandle,1))*256^2+asc(fread(filehandle,1))*256^3 nfldlen=asc(fread(filehandle,1)) && byte 17 * if the field is type N F B or Y find out how many decimals there are DO case CASE cfldtype$'NFBY' nflddec=asc(fread(filehandle,1)) && byte 18 nfldflag=asc(fread(filehandle,1)) && byte 19 =fseek(filehandle,13,1) && skip 13 bytes CASE cfldtype='I' nflddec=asc(fread(filehandle,1)) && byte 18 nfldflag=asc(fread(filehandle,1)) && byte 19 nAutoIncrNextVal = ASC(FREAD(filehandle,1)) + ASC(FREAD(filehandle,1))* 256 + ; ASC(FREAD(filehandle,1))* 256^2 + ASC(FREAD(filehandle,1)) * 256^3 && bytes 20,21,22 and 23 nAutoIncrStepVal = ASC(FREAD(filehandle,1)) && byte 24 =fseek(filehandle,8,1) && skip 8 bytes OTHERWISE nfldflag=asc(fread(filehandle,1)) && byte 18 =fseek(filehandle,14,1) && skip 14 bytes ENDCASE ? tran(nfldcnt,'@L 9999'),padr(cfield,11) ?? ' '+ cfldtype + ' ' ?? str(nfldlen,5)+iif(cfldtype='N','.'+ltrim(str(nflddec)),' ') ?? str(nfldpos,7) Do case case nfldflag = 1 ?? ' System column ' case nfldflag = 2 ?? ' Null values ok' case nfldflag = 4 ?? ' Binary column ' CASE nfldflag = 6 ?? ' Null val & bin' CASE nfldflag = 12 ?? ' Autoincr. ' otherwise ?? ' ' ENDCASE IF nAutoIncrNextVal>0 ?? PADR(nAutoIncrNextVal,10)+' '+STR(nAutoIncrStepVal,3) ENDIF * test field length specificatons DO CASE CASE cfldtype$'DTBY' && these fields all should have a length of 8 bytes IF nfldlen<>8 ?? IIF(dbfhdr[1]=49,' ', SPACE(30))+'Invalid fieldlength, length should be 8' nFldProblem=nFldProblem+1 ENDIF CASE cfldtype$'GIMP' && these fields all should have a length of 4 bytes IF nfldlen<>4 ?? IIF(dbfhdr[1]=49,' ', SPACE(30))+'Invalid fieldlength, length should be 4' nFldProblem=nFldProblem+1 ENDIF CASE cfldtype='C' && this field should have a length of 1-254 bytes IF !BETWEEN(nfldlen,1,254) ?? IIF(dbfhdr[1]=49,' ', SPACE(30))+'Invalid fieldlength, length should be 1-254' nFldProblem=nFldProblem+1 ENDIF CASE cfldtype$'NF' && these fields all should have a length of 1-20 bytes IF !BETWEEN(nfldlen,1,20) ?? IIF(dbfhdr[1]=49,' ', SPACE(30))+' Invalid fieldlength, length should be 1-20' nFldProblem=nFldProblem+1 IF nflddec> 18 && field decimals must be fieldlen - 2 maximal ?? ' Invalid number of decimals, max value is 18' nFldProblem=nFldProblem+1 ENDIF ELSE && field length in normal range, check number of decimals IF nflddec>0 && field decimals defined and fieldlen OK IF nfldlen - nflddec< 2 && field decimals must be fieldlen - 2 maximal ?? IIF(dbfhdr[1]=49,' ', SPACE(30))+' Invalid number of decimals, max value is '+LTRIM(STR(nfldlen - 2)) nFldProblem=nFldProblem+1 ENDIF ENDIF ENDIF CASE cfldtype='L' && this field should have a length of 1 byte IF nfldlen<>1 ?? IIF(dbfhdr[1]=49,' ', SPACE(30))+'Invalid fieldlength, length should be 1' nFldProblem=nFldProblem+1 ENDIF ENDCASE enddo =fseek(filehandle,1,1) && skip one byte nassdbc=asc(fread(filehandle,1)) ? '----------------------------------------------------------------------' if nassdbc=0 ? rdfile+' is not associated with a DBC' else =fseek(filehandle,-1,1) && skip back one byte cassdbc=fread(filehandle,263) nsppos=at(chr(0),cassdbc) if nsppos>0 cassdbc=left(cassdbc,nsppos-1) endif ? rdfile+' is associated with '+cassdbc endif endcase ? ? 'Some checks...' nfilesizediff = nrecords*nreclen+nposrec1 - nfilesize ? 'Physical filesize ok :', ; IIF(nfilesizediff=0,'Yes', 'NO, '+ ; IIF(nfilesizediff>0,'TRUNCATED ','TOO LARGE ') ; +'('+LTRIM( STR( ABS(nfilesizediff) ) )+' bytes)' ) ? 'Last update date valid :', + IIF(!EMPTY(dtmp),'Yes','No') ? 'Header record terminator (0x0D) found at:', LTRIM(STR( nEnddef)), IIF(nEnddef = nposrec1 - 1 -iif(lisvfp,263,0),' OK',' Error in header') ? 'Record length according to fielddefinitions is '+ltrim(STR(nfldpos+nfldlen))+' which is '+IIF(nfldpos+nfldlen = nreclen,'OK','WRONG') ? 'There were '+IIF(nFldProblem>0,LTRIM(STR(nFldProblem)),'no')+' problems with the field definitions' ? =fclose(filehandle) && close the table * restore some original settings that were changed possibly.... SET DATE (cSetDate) && restore original set date setting SET CENTURY &cSetCentury && restore original set century setting RELEASE ALL RETURN *********************************************************** PROCEDURE cdxmemdbc do case case dbfhdr[29]=0 lhascdx=.f. lhasmem=.f. lisdbc=.f. case dbfhdr[29]=1 lhascdx=.t. lhasmem=.f. lisdbc=.f. case dbfhdr[29]=2 lhascdx=.f. lhasmem=.t. lisdbc=.f. case dbfhdr[29]=3 lhascdx=.t. lhasmem=.t. lisdbc=.f. case dbfhdr[29]=4 lhascdx=.f. lhasmem=.f. lisdbc=.t. case dbfhdr[29]=5 lhascdx=.t. lhasmem=.f. lisdbc=.t. case dbfhdr[29]=6 lhascdx=.f. lhasmem=.t. lisdbc=.t. case dbfhdr[29]=7 lhascdx=.t. lhasmem=.t. lisdbc=.t. otherwise lhascdx=.f. lhasmem=.f. lisdbc=.f. lcdxmemdbcError=.t. endcase return procedure getfname CLEAR SET STEP ON rdfile = GETFILE("dbf") *!* @ 5,5 say 'Enter dbfname to investigate: ' get rdfile pict '@!' *!* read rdfile=alltrim(rdfile) if len(rdfile)=0 return endif CLEAR PUBLIC filehandle filehandle=FOPEN(rdfile) && Open the file if filehandle < 0 wait(rdfile+' NOT FOUND') return endif return procedure readheader nfilesize =FSEEK(filehandle, 0 ,2) && move pointer to last byte to get filesize =FSEEK(filehandle, 0,0) && Move pointer to first byte bytecount=1 do while bytecount < 33 dbfhdr[bytecount] = asc(fgets(filehandle,1)) * if you want to see the contents of these bytes * remove the * from the next line * ? bytecount,dbfhdr[bytecount] bytecount=bytecount+1 enddo return FUNCTION FileType parameters ctyp public c_type do case case ctyp=2 c_type='Foxbase' case ctyp=3 c_type='Foxbase/Foxpro/dBaseIII/IV no memo' case ctyp=48 c_type='Visual Foxpro' case ctyp=49 c_type='Visual Foxpro 8+ AutoIncr' case ctyp=50 c_type='Visual Foxpro 9+,Varchar,Varbinary or Blob-enabled' case ctyp=67 c_type='dBase IV SQL table no memo' case ctyp=99 c_type='dBase IV SQL system file no memo' case ctyp=131 c_type='Foxbase/dBaseIII Plus with memo' case ctyp=139 c_type='dBaseIV with memo' case ctyp=203 c_type='dBaseIV SQL table with memo' case ctyp=245 c_type='Foxpro 2.x with memo' case ctyp=251 c_type='Foxbase' otherwise c_type='Unknown or invalid type' endcase return c_type FUNCTION ShowCodePageInfo PARAMETERS nCP public cCP DO case CASE nCP = 0 && 0x00 cCP = 'No codepage defined' CASE nCP = 1 && 0x01 cCP = 'Codepage 437 US MSDOS' CASE nCP = 2 && 0x02 cCP = 'Codepage 850 International MS-DOS' CASE nCP = 3 && 0x03 cCP = 'Codepage 1252 Windows ANSI' CASE nCP = 4 && 0x04 cCP = 'Codepage 10000 Standard MacIntosh' CASE nCP = 100 && 0x64 cCP = 'Codepage 852 Easern European MS-DOS' CASE nCP = 101 && 0x65 cCP = 'Codepage 866 Russian MS-DOS' CASE nCP = 102 && 0x66 cCP = 'Codepage 865 Nordic MS-DOS' CASE nCP = 103 && 0x67 cCP = 'Codepage 861 Icelandic MS-DOS' CASE nCP = 104 && 0x68 cCP = 'Codepage 895 Kamenicky (Czech) MS-DOS' CASE nCP = 105 && 0x69 cCP = 'Codepage 620 Mazovia (Polish) MS-DOS' CASE nCP = 106 && 0x6A cCP = 'Codepage 737 Greek MS-DOS (437G)' CASE nCP = 107 && 0x6B cCP = 'Codepage 857 Turkish MS-DOS' CASE nCP = 120 && 0x78 cCP = 'Codepage 950 Chinese (Hong Kong SAR, Taiwan) Windows' CASE nCP = 121 && 0x79 cCP = 'Codepage 949 Korean Windows' CASE nCP = 122 && 0x7A cCP = 'Codepage 936 Chinese (PRC, Singapore) Windows' CASE nCP = 123 && 0x7B cCP = 'Codepage 932 Japanese Windows' CASE nCP = 124 && 0x7C cCP = 'Codepage 874 Thai Windows' CASE nCP = 125 && 0x7D cCP = 'Codepage 1255 Hebrew Windows' CASE nCP = 126 && 0x7E cCP = 'Codepage 1256 Arabic Windows' CASE nCP = 150 && 0x96 cCP = 'Codepage 10007 Russian MacIntosh' CASE nCP = 151 && 0x97 cCP = 'Codepage 10029 MacIntosh EE' CASE nCP = 152 && 0x98 cCP = 'Codepage 10006 Greek MacIntosh' CASE nCP = 200 && 0xC8 cCP = 'Codepage 1250 Eastern European Windows' CASE nCP = 201 && 0xC9 cCP = 'Codepage 1251 Russian Windows' CASE nCP = 202 && 0xCA cCP = 'Codepage 1254 Turkish Windows' CASE nCP = 203 && 0xCB cCP = 'Codepage 1253 Greek Windows' OTHERWISE cCP = 'Unknown / invalid codepage' ENDCASE RETURN cCP Mike Gagnon

ducker88 · Answer

bonjour,
merci, mais y'a pas plus simple ? 
Bon bah je vais voir ca. Merci beaucoup

duck88

michelatoutfox · Answer

Bonjour,

regarde si ceci te convient:
http://www.atoutfox.org/articles.asp?ACTION=FCONSULTER&ID=0000000221


les fichiers ne sont en effet pas les mêmes, et l'information concernant la version de fox sous laquelle ils sont est stockée dans le header de la table:


extrait de l'aide de VFP9:
Table Header Record Structure


Byte offset |
Description |

----

0,
File type: 0x02

FoxBASE: 0x03

FoxBASE+/Dbase III plus, no memo: 0x30

Visual FoxPro: 0x31

Visual FoxPro, autoincrement enabled: 0x32

Visual FoxPro, Varchar, Varbinary, or Blob-enabled: 0x43

dBASE IV SQL table files, no memo: 0x63

dBASE IV SQL system files, no memo: 0x83

FoxBASE+/dBASE III PLUS, with memo: 0x8B

dBASE IV with memo: 0xCB

dBASE IV SQL table files, with memo: 0xF5

FoxPro 2.x (or earlier) with memo: 0xFB

FoxBASE,

----

1 - 3,
Last update (YYMMDD),

----

4 – 7,
Number of records in file,

----

8 – 9,
Position of first data record,

----

10 – 11,
Length of one data record, including delete flag,

----

12 – 27,
Reserved,

----

28,
Table flags: 0x01   file has a structural .cdx 0x02   file has a Memo field 0x04   file is a database (.dbc) This byte can contain the sum of any of the above values. For example, the value 0x03 indicates the table has a structural .cdx and a Memo field.,

----

29,
Code page mark,

----

30 – 31,
Reserved, contains 0x00,

----

32 – n,
Field subrecords The number of fields determines the number of field subrecords. One field subrecord exists for each field in the table.,

----

n+1,
Header record terminator (0x0D),

----

n+2 to n+264,
A 263-byte range that contains the backlink, which is the relative path of an associated database (.dbc) file, information. If the first byte is 0x00, the file is not associated with a database. Therefore, database files always contain 0x00.

ducker88 · Answer

Bonjour Michel,

Merci pour ce petit programme, c'est exactement ce qu'il me fallait.
Le programme me retourne 30 pour le type de fichier, j'en conclu donc par ces informations qu'ils sont du type FoxBASE+/Dbase III plus, no memo.

Existe t'il une solution pour faire passer ces fichier en 0x43 c'est a dire en fichier foxpro ?

duck88

Difference entre foxpro et visual foxpro

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