Comment puis-je lire et écrire CSV dans une manière semblable au NET FileHelpers?

C'est assez basique, mais TStringList a Delimiter, DelimitedText, et QuoteChar propriétés, qui répondent à certaines de ces questions.

Mis à jour pour ajouter, par commentaires: Ne pas être tenté par le CommaText de la propriété, qui a un peu surprenant limites pour la compatibilité ascendante avec archaïque versions de Delphi.

Voici quelque code que j'ai écrit qui lit les fichiers CSV, il gère les retours chariot à l'intérieur de citations ainsi.

unit CSV;
interface
uses
SysUtils, Generics.Collections, IOUtils;
type
TParseState = (psRowStart, psFieldStart, psUnquotedFieldData,
psQuotedFieldData, psQFBranch, psEndOfQuotedField, psQFEndSearch,
psEndOfLine, psEndOfFile);
TCSVField = class
strict private
FText: String;
public
constructor Create;
destructor Destroy; override;
property Text: string read FText write FText;
procedure Clear;
end;
TCSVFieldList = class(TObjectList<TCSVField>)
public
function AddField(const AText: string): TCSVField;
procedure ClearFields;
end;
TCSVRow = class
strict private
FFields: TCSVFieldList;
public
constructor Create;
destructor Destroy; override;
property Fields: TCSVFieldList read FFields;
end;
TCSVParser = class
strict private
FRow: TCSVRow;
FContent: String;
FCIdx: Integer;
FParseState: TParseState;
FEOF: Boolean;
procedure ParseRow;
public
function First: Boolean;
function EOF: Boolean;
function Next: Boolean;
procedure OpenFile(AFileName: String);
procedure OpenText(const AText: string);
property Row: TCSVRow read FRow;
constructor Create;
destructor Destroy; override;
end;
implementation
{implementation of TCSVField}
procedure TCSVField.Clear;
begin
FText:= '';
end;
constructor TCSVField.Create;
begin
inherited Create;
end;
destructor TCSVField.Destroy;
begin
inherited Destroy;
end;
{implementation of TCSVRow}
constructor TCSVRow.Create;
begin
inherited Create;
FFields:= TCSVFieldList.Create;
end;
destructor TCSVRow.Destroy;
begin
FreeAndNil(FFields);
inherited Destroy;
end;
{implementation of TCSVParser}
constructor TCSVParser.Create;
begin
inherited Create;
FRow:= TCSVRow.Create;
FCIdx:= 1;
FParseState:= psEndOfFile;
end;
destructor TCSVParser.Destroy;
begin
FreeAndNil(FRow);
inherited Destroy;
end;
function TCSVParser.EOF: Boolean;
begin
Result:= FEOF;
end;
function TCSVParser.First: Boolean;
begin
FEOF:= False;
FCIdx:= 1;
FParseState:= psRowStart;
Result:= Next;
end;
function TCSVParser.Next: Boolean;
begin
if not EOF then
ParseRow;
Result:= not EOF;
end;
procedure TCSVParser.OpenFile(AFileName: String);
begin
OpenText(TFile.ReadAllText(AFileName));
end;
procedure TCSVParser.OpenText(const AText: string);
begin
FContent:= AText;
FRow.Fields.Clear;
First;
end;
procedure TCSVParser.ParseRow;
var
FieldIdx: Integer;
procedure AddField(const AText: string);
begin
if FieldIdx > FRow.Fields.Count-1 then
FRow.Fields.AddField(AText)
else
FRow.Fields[FieldIdx].Text:= AText;
Inc(FieldIdx);
end;
var
FieldText: string;
Curr: Char;
LastIdx: Integer;
begin
if FParseState = psEndOfFile then
begin
FEOF:= True;
FRow.Fields.ClearFields;
Exit;
end;
if not (FParseState in [psRowStart]) then
raise Exception.Create('ParseRow requires ParseState = psRowState');
FieldIdx:= 0;
FRow.Fields.ClearFields;
LastIdx:= Length(FContent);
while True do
begin
case FParseState of
psRowStart:
begin
if FCIdx > LastIdx then
begin
FEOF:= True;
FParseState:= psEndOfFile;
end
else
begin
FParseState:= psFieldStart;
end;
Dec(FCIdx); // do not consume
end;
psFieldStart:
begin
FieldText:= '';
if FContent[FCIdx] = '"' then
FParseState:= psQuotedFieldData
else
begin
FParseState:= psUnquotedFieldData;
Dec(FCIdx); // do not consume
end;
end;
psUnquotedFieldData:
begin
if FCIdx > LastIdx then
begin
AddField(FieldText);
FParseState:= psEndOfFile;
end
else
begin
Curr:= FContent[FCIdx];
case Curr of
#13, #10:
begin
AddField(FieldText);
FParseState:= psEndOfLine;
end;
',':
begin
AddField(FieldText);
FParseState:= psFieldStart;
end;
else
FieldText:= FieldText + Curr;
end;
end;
end;
psQuotedFieldData:
begin
if FCIdx > LastIdx then
raise Exception.Create('EOF in quoted Field.');
Curr:= FContent[FCIdx];
if Curr = '"' then
FParseState:= psQFBranch
else
FieldText:= FieldText + Curr;
end;
psQFBranch:
begin
Curr:= FContent[FCIdx];
if Curr = '"' then
begin
FieldText:= FieldText + Curr;
FParseState:= psQuotedFieldData;
end
else
begin
AddField(FieldText);
FParseState:= psEndOfQuotedField;
Dec(FCIdx); // do not consume
end;
end;
psEndOfQuotedField:
begin
if FCIdx > LastIdx then
FParseState:= psEndOfFile
else
begin
Curr:= FContent[FCIdx];
if CharInSet(Curr, [#13, #10]) then
FParseState:= psEndOfLine
else
begin
FParseState:= psQFEndSearch;
Dec(FCIdx); // do not consume
end;
end;
end;
psQFEndSearch:
begin
if FCIdx > LastIdx then
FParseState:= psEndOfFile
else
begin
Curr:= FContent[FCIdx];
if CharInSet(Curr, [#13, #10]) then
FParseState:= psEndOfLine
else if Curr = ',' then
FParseState:= psFieldStart;
// skips white space or other until end
end;
end;
psEndOfLine:
begin
if FCIdx > LastIdx then
FParseState:= psEndOfFile
else
begin
Curr:= FContent[FCIdx];
if not CharInSet(Curr, [#13, #10]) then
begin
FParseState:= psRowStart;
Break; // exit loop, we are done with this row
end;
end;
end;
psEndOfFile:
begin
Break;
end;
end;
Inc(FCIdx);
end;
end;
{ TCSVFieldList }
function TCSVFieldList.AddField(const AText: string): TCSVField;
begin
Result:= TCSVField.Create;
Add(Result);
Result.Text:= AText;
end;
procedure TCSVFieldList.ClearFields;
var
F: TCSVField;
begin
for F in Self do
F.Clear;
end;
end.

Mes fonctions

function ParseCSVString(s: string; const delimiter: Char = ','; const enclosure: Char = '"'): TStrings;
var
i,len: Integer;
f: string;
inQuoted: Boolean;
begin
Result := TStringList.Create;
len := Length(s);
if len = 0 then Exit;
//Test,Test;"Test;Test";"Test""Test";;
f := '';
inQuoted := False;
i:=0;
while i < len do
begin
Inc(i);
if s[i] = enclosure then
begin
if inQuoted and (i<len) and (s[i+1] = enclosure) then
begin
f := f + '"';
i:=i+1;
end
else
inQuoted := not inQuoted;
end
else if s[i] = delimiter then
begin
if inQuoted then
f := f+s[i]
else
begin
Result.Add(f);
inQuoted := false;
f := '';
end;
end
else
f := f + s[i];
end;
Result.Add(f);
end;
function EscapeCSVString(s: string; const delimiter: Char = ','; const enclosure: Char = '"'): string;
var
i: Integer;
begin
Result := StringReplace(s,enclosure,enclosure+enclosure,[rfReplaceAll]);
if (Pos(delimiter,s) > 0) OR (Pos(enclosure,s) > 0) then
Result := enclosure+Result+enclosure;
end;