OneDbf class structure:
~~~~~~~~~~~~~~~~~~~~~~~
create class OneDbf
  export:
  var File       //""
  var Name       //""
  var Struc      //{}
  var Pict       //{}
  var PreBlock   //{}
  var PostBlock  //{}
  var Ntx        //{}
  var Rel        //{}
  method New=OneDbfNew                 //o:New() --> self
  method Init=OneDbfInit               //o:Init() --> true
  method Create=OneDbfCreate           //o:Create(lContinue) --> true/false
  method Open=OneDbfOpen               //o:Open(lShared,lContinue,lNew) --> true/false
  method NtxOpen=OneDbfNtxOpen         //o:NtxOpen(lContinue) --> true/false
  method ReIndex=OneDbfReIndex         //o:ReIndex(lContinue) --> true/false
  method Pack=OneDbfPack               //o:Pack(lContinue) --> true/false
  method Zap=OneDbfZap                 //o:Zap(lContinue) --> true/false
  method SetRelation=OneDbfSetRelation //o:SetRelation() --> true
  method AddField=OneDbfAddField       //o:AddField(cName,cType,nLen,nDec) --> true
  method AddNtx=OneDbfAddNtx           //o:AddNtx(cName,cFile,cKey,lUnique,lUser) --> true
  method AddRelation=OneDbfAddRelation //o:AddRelation(xKey,cAlias,nOrder) --> true
  method Picture=OneDbfPicture         //o:Picture(cPict) --> true
  method Range=OneDbfRange             //o:Range(nLo,nHi) --> true
  method When=OneDbfWhen               //o:When(bWhen) --> true
  method Valid=OneDbfValid             //o:Valid(bValid) --> true
  method ChValid=OneDbfChValid         //o:ChValid(bValid) --> true
  endclass