Mega Code Archive
Sscanf in delphi
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Title: sscanf in delphi?
Question: sscanf in delphi?
Answer:
I have found this unit quite useful, but there may be a problem with the %s tag
since its use has generated errors on occasion.
unit Scanf;
interface
uses
SysUtils;
type
EFormatError = class(ExCeption);
function Sscanf(const s: string; const fmt: string; const Pointers: array of Pointer): Integer;
implementation
{ Sscanf parses an input string. The parameters ...
s - input string to parse
fmt - 'C' scanf-like format string to control parsing
%d - convert a Long Integer
%f - convert an Extended Float
%s - convert a string (delimited by spaces)
other char - increment s pointer past "other char"
space - does nothing
Pointers - array of pointers to have values assigned
result - number of variables actually assigned
for example with ...
Sscanf('Name. Bill Time. 7:32.77 Age. 8',
'. %s . %d:%f . %d', [@Name, @hrs, @min, @age]);
You get ...
Name = Bill hrs = 7 min = 32.77 age = 8 }
function Sscanf(const s: string; const fmt: string; const Pointers: array of Pointer): Integer;
var
i, j, n, m: integer;
s1: string;
L: LongInt;
X: Extended;
function GetInt: Integer;
begin
s1 := '';
while (s[n] = ' ') and (Length(s) n) do
inc(n);
while (s[n] in ['0'..'9', '+', '-'])
and (Length(s) = n) do
begin
s1 := s1 + s[n];
inc(n);
end;
Result := Length(s1);
end;
function GetFloat: Integer;
begin
s1 := '';
while (s[n] = ' ') and (Length(s) n) do
inc(n);
while (s[n] in ['0'..'9', '+', '-', '.', 'e', 'E'])
and (Length(s) = n) do
begin
s1 := s1 + s[n];
inc(n);
end;
Result := Length(s1);
end;
function GetString: Integer;
begin
s1 := '';
while (s[n] = ' ') and (Length(s) n) do
inc(n);
while (s[n] ' ') and (Length(s) = n) do
begin
s1 := s1 + s[n];
inc(n);
end;
Result := Length(s1);
end;
function ScanStr(c: Char): Boolean;
begin
while (s[n] c) and (Length(s) n) do
inc(n);
inc(n);
if (n Result := True
else Result := False;
end;
function GetFmt: Integer;
begin
Result := -1;
while (TRUE) do
begin
while (fmt[m] = ' ') and (Length(fmt) m) do
inc(m);
if (m = Length(fmt)) then
break;
if (fmt[m] = '%') then
begin
inc(m);
case fmt[m] of
'd': Result := vtInteger;
'f': Result := vtExtended;
's': Result := vtString;
end;
inc(m);
break;
end;
if (ScanStr(fmt[m]) = False) then
break;
inc(m);
end;
end;
begin
n := 1;
m := 1;
Result := 0;
for i := 0 to High(Pointers) do
begin
j := GetFmt;
case j of
vtInteger:
begin
if GetInt 0 then
begin
L := StrToInt(s1);
Move(L, Pointers[i]^, SizeOf(LongInt));
inc(Result);
end
else
break;
end;
vtExtended:
begin
if GetFloat 0 then
begin
X := StrToFloat(s1);
Move(X, Pointers[i]^, SizeOf(Extended));
inc(Result);
end
else
break;
end;
vtString:
begin
if GetString 0 then
begin
Move(s1, Pointers[i]^, Length(s1) + 1);
inc(Result);
end
else break;
end;
else
break;
end;
end;
end;
end.
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