Импорт большого CSV файла
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Скачивание файла.
Размер: неизвестно (скачено 45%).



var s: String; f: TextFile;
AssignFile(f, 'D:\INPUT.TXT);
Reset(f);
while not EOF(f) do
begin
ReadLn(s, f);
ShowMessage(GetField(s, 1)); {The first field}
ShowMessage(GetField(s, 6)); {The sixth field}
ShowMessage(GetField(s, 25)); {will return '' if no 25 column...}
end;
CloseFile(f);

{ ==== This function will return a field from a delimited string. ==== }
function GetField(InpString: String; fieldpos: Integer): String;
var
c: Char;
curpos, i: Integer;
begin
curpos := 1;
for i := 1 to fieldpos do
begin
result := ''; if curpos > Length(InpString) then Break;
repeat
c := InpString[curpos]; Inc(curpos, 1);
if (c = '"') or (c = #13) or (c = #10) then c := ' ';
if c <> ',' then result := result + c;
until (c = ',') or (curpos > Length(InpString))
end;
if (curpos > Length(InpString)) and (i 1 then Delete(inp_str, 1, i - 1);
for i := Length(inp_str) downto 1 do if inp_str[i] <> ' ' then Break;
if i < Length(inp_str) then Delete(inp_str, i + 1, Length(inp_str));
result := inp_str;
if result = ' ' then result := '';
end;