Strings Again

[garlar27]

Did anybody suggest using TStringList.CommaText?

Didn't know about it 

[jamie]

He needs a parsing "GET" function, one that ignores spaces as it builds a captured string until a comma is hit and
thus remembers where it was the last time for the next read of the string.

For example

Var
 X:Integer;
 S:Sting;
Begin
 X ;= 0; first initial setting for the line.

 S:= GET(X);
 While S <> '' Do begin
  begin
    // do something with S;
   S := GET(X); // the Get function will auto increment for the next location.
 End;


The GET function may also consider accepting spaces for the content if there was a quote started.

I am sure with all the powers to be here, someone can hack out a function like that.. 

 

[JLWest]

Have been trying to make the function supplied by Handoko but it only eturns the first field.

It close but I can't figure out why it won't return the second or fourth field.

Attached is a self contained demo using the function.

Code: Pascal  [Select][+][-]

1.      function TForm1.GetFieldNo(const aText: String; aFieldNo: Integer; out fieldCount: Integer): String;
2.     const
3.       Comma = ',';
4.     type
5.       TPosArray = array[1..9] of Integer;
6.     var
7.       txt: String;
8.       arr:  TPosArray;
9.       i: Integer;
10.     begin
11.       fieldCount := 0;
12.       txt := Trim(aText);
13.       arr := Default(TPosArray);
14.       if (Length(txt) < 2) or (Pos(Comma, txt) = 0) or (aFieldNo < 1) then
15.         Exit('');
16.       for i := 1 to Length(txt) do
17.         if txt[i] = Comma then
18.           begin
19.             Inc(fieldCount);
20.             arr[fieldCount] := i;
21.           end;
22.       if aFieldNo > Succ(fieldCount) then
23.         Exit('');
24.       case aFieldNo = 1 of
25.         True:  Result := Trim(Copy(txt, 1, Pred(arr[1])));
26.         False: begin
27.                  if aFieldNo = Succ(fieldCount) then
28.                    Result := Trim(Copy(text, Succ(arr[fieldCount]), Length(text)))
29.                  else Result := Trim(Copy(text, Succ(arr[Pred(aFieldNo)]), Pred(arr[aFieldNo] - arr[Pred(aFieldNo)])));
30.                end;
31.       end;
32.       Inc(fieldCount);
33.     end;                        

 

[wp]

JLWest, did you consider Bart's suggestion with TStringList in reply #14? It works perfectly:

Code: Pascal  [Select][+][-]

1. program Project1;
2.  
3. uses
4.   Classes;
5.  
6. const
7.   s =  'LAN  ,   YSSY  ,   NZAA  ,   B789_LAN_LATAM  ,  0010  ,   LA800  ,   CC-BGA  ,  0  ,0325';
8.  
9. var
10.   i: Integer;
11.   L: TStringList;
12. begin
13.   L := TStringList.Create;
14.   try
15.     L.CommaText := s;
16.     WriteLn(L.count, ' items:');
17.     for i:=0 to L.Count-1 do
18.       WriteLn('"', L[i], '"');
19.   finally
20.     L.Free;
21.   end;
22.  
23.   ReadLn;
24. end.

Output (the quotes were added to show whether the spaces are trimmed correctly):

9 items:
"LAN"
"YSSY"
"NZAA"
"B789_LAN_LATAM"
"0010"
"LA800"
"CC-BGA"
"0"
"0325"

[jamie]

as WP pointed out, that will work fine but since I've already banged out some code I just have to post it here 

Code: Pascal  [Select][+][-]

1. { TForm1 }
2. Function GET(Const InputStr:String;Var X :Integer):String;
3. begin
4.   Result := '';
5.   Repeat
6.    Inc(X); // move to next char;
7.    If X > Length(Inputstr) Then
8.     Begin
9.      Dec(X);
10.      Exit;// done;
11.     End;
12.    If Not (InputStr[X] in[' ',',']) Then Result := Result+inputstr[x];
13.   Until InputStr[X] = ',';
14. end;
15.  
16. procedure TForm1.Button1Click(Sender: TObject);  //Test run..
17. Var
18.   A:Array[1..20] of string;
19.   X,Aindex:Integer;
20.   S,B:String;
21. begin
22.    X := 0; Aindex := 0;
23.    S:= 'Some_Test_String , To_See_if_it_Works  ,END'; //Fake string for test.
24.    B := Get(S,X);  //Get the first one;
25.    While B <> '' do
26.     Begin
27.       Inc(AIndex);    //Number of entries of string;
28.       A[AIndex] := B;  //Store each one in a string by itself;
29.       Caption := Caption+B; //Use CAPTION as a repository and debug display.
30.       B := Get(S,X);  //Get next;
31.     end;
32. // at this point the aIndex should be 1 or more, if 0 then nothing in string;
33. // Also after each read, X will be resting at a ',' or length of input string, which means no more.
34. end;                                                                                  
35.  

[lucamar]

This one should work too, but I didn't test it

Code: Pascal  [Select][+][-]

1. function CutLoc(aInt: Integer; const aStr: string): Integer;
2. var
3.   Loc, Count: Integer;
4. begin
5.   Count := 0;
6.   Loc := 1;
7.   repeat
8.     { Find the next "," from position Loc }
9.     Loc := PosEx(',', aStr, Loc);
10.     { Found one? update the count of commas
11.       and the next starting position}
12.     if Loc > 0 then begin
13.       Inc(Count);
14.       Inc(Loc);
15.     end;
16.   until (Count = aInt) or (not (Loc in [1..Length(aStr)]));
17.   if Count <> aInt then
18.     { Not enough commas! Do something }
19.   else
20.     Result := Loc;
21. end;
22.  

[JLWest]

JLWest, did you consider Bart's suggestion with TStringList in reply #14? It works perfectly:

Code: Pascal  [Select][+][-]

1. program Project1;
2.  
3. uses
4.   Classes;
5.  
6. const
7.   s =  'LAN  ,   YSSY  ,   NZAA  ,   B789_LAN_LATAM  ,  0010  ,   LA800  ,   CC-BGA  ,  0  ,0325';
8.  
9. var
10.   i: Integer;
11.   L: TStringList;
12. begin
13.   L := TStringList.Create;
14.   try
15.     L.CommaText := s;
16.     WriteLn(L.count, ' items:');
17.     for i:=0 to L.Count-1 do
18.       WriteLn('"', L[i], '"');
19.   finally
20.     L.Free;
21.   end;
22.  
23.   ReadLn;
24. end.

Output (the quotes were added to show whether the spaces are trimmed correctly):

9 items:
"LAN"
"YSSY"
"NZAA"
"B789_LAN_LATAM"
"0010"
"LA800"
"CC-BGA"
"0"
"0325"

I have tried for a couple of days to get this to work. And I have trouble with each suggestion.
I have got the line parsed for 7 of the 9 fields , but the 8th and 9th fields give me a lot of trouble. A record will always have 8 fields but the 9 field is optional.

Now I'm looking at the TStringList solution.

It looks simple.
Will something like this workl

I read a record from the file: TFRecord

L := TStringList.Create;
 try
    L.CommaText := TFRecord;
for i:=0 to L.Count-1 do Begin <----------------- going thru the list of fields
      Field := L;                 <-------------------- Field is a String             
     ValidField :=  VerifyField(Field); <------------ValidField is a Boolean
end; <----------------------------------------------End of list
  finally
    L.Free;

I'll try this tomorrow.

[wp]

L := TStringList.Create;
 try
    L.CommaText := TFRecord;
for i:=0 to L.Count-1 do Begin <----------------- going thru the list of fields
      Field := L;                 <-------------------- Field is a String             
     ValidField :=  VerifyField(Field); <------------ValidField is a Boolean
end; <----------------------------------------------End of list
  finally
    L.Free;

This actually is correct although the line "Field := L" looks wrong. This is because the forum software swallows the character i enclosed by square brackets. I am repeating your code here using the index j instead of i to demonstrate that it does not contain a line "Field := L"

L := TStringList.Create;
 try
    L.CommaText := TFRecord;
for j:=0 to L.Count-1 do Begin <----------------- going thru the list of fields
      Field := L[j];                 <-------------------- Field is a String             
     ValidField :=  VerifyField(Field); <------------ValidField is a Boolean
end; <----------------------------------------------End of list
  finally
    L.Free;
end;

In general it would be better to enclose your source code by [code ] tags (Select it and click on the # button above the edit field):

Code: Pascal  [Select][+][-]

1. L := TStringList.Create;
2.  try
3.     L.CommaText := TFRecord;
4. for i:=0 to L.Count-1 do Begin <----------------- going thru the list of fields
5.       Field := L[i];                 <-------------------- Field is a String            
6.      ValidField :=  VerifyField(Field); <------------ValidField is a Boolean
7. end; <----------------------------------------------End of list
8.   finally
9.     L.Free;
10.   end;
11.  

[JLWest]

Yea, I noticed I could't get the '[' ']' to display.

I'm about to build a little test program to try TStringList. Let you know.

Thanks.

[JLWest]

Code: Pascal  [Select][+][-]

1.  function TForm1.ProcessOneRecord(aTFrec : String) : XferRecord;
2.   Var
3.     Lst : TStringList;
4.     XFerRec : XferRecord;
5.     TFRecord : String = '';
6.     Field : String;
7.     Flds : Integer;
8.     Idx : Integer;
9.   Begin
10.    Lst := TStringList.Create;
11.   try
12.      Lst.CommaText := aTFrec;
13.      Flds := Lst.Count;
14.      XFerRec.TxtRec:= aTFrec;
15.      XFerRec.Fields:= Flds;
16.  
17.     for Idx:= 0 to Lst.Count-1 do begin
18.      Field :=  Lst[Idx];
19.      XFerRec := UpdateXFerRecord(Field,Idx,XFerRec);
20.      ShowField(Field);
21.     end;
22.   finally
23.     Lst.Free;
24.     Result := XFerRec;
25.   end;
26.  end;                              

Got this working great.
 
It's the "Lst.CommaText := aTFrec;" that does all the heavy lifting I think.

Have to try it on a record that looks like the following:

  'LAN,YSSY,NZAA,B789_LAN_LATAM, 0010,LA800,CC-BGA,0'

WOW.

Thanks

[garlar27]

Maybe it's a little late but
Have you tried something like this (though I don´t know how it will work if one field is missing):

Code: Pascal  [Select][+][-]

1. uses CsvDocument;
2.  
3. type
4.    TFlight = record
5.       Field01: string;
6.       Field02: string;
7.       Field03: string;
8.       Field04: string;
9.       Field05: string;
10.       Field06: string;
11.       Field07: string;
12.       Field08: string;
13.       Field09: string;
14.    end;
15.  
16. procedure ProcessData(const AFile: string);
17. var
18.    CSVDocument : TCSVDocument;
19.    ind: Integer;
20.    AFlight: TFlight;
21. begin
22.    CSVDocument := nil;
23.    try
24.       CSVDocument := TCSVDocument.Create;
25.  
26.       CSVDocument.LoadFromFile(AFile);
27.       for ind := 1 to CSVDocument.RowCount - 1 do begin
28.          AFlight.Field01 := Trim(CSVDocument.Cells[0,ind]);
29.          AFlight.Field02 := Trim(CSVDocument.Cells[1,ind]);
30.          AFlight.Field03 := Trim(CSVDocument.Cells[2,ind]);
31.          AFlight.Field04 := Trim(CSVDocument.Cells[3,ind]);
32.          AFlight.Field05 := Trim(CSVDocument.Cells[4,ind]);
33.          AFlight.Field06 := Trim(CSVDocument.Cells[5,ind]);
34.          AFlight.Field07 := Trim(CSVDocument.Cells[6,ind]);
35.          AFlight.Field08 := Trim(CSVDocument.Cells[7,ind]);
36.          AFlight.Field09 := Trim(CSVDocument.Cells[8,ind]);
37.          // Do something with AFlight
38.       end; {<--- del for ind }
39.    finally
40.       FreeAndNil(CSVDocument);
41.    end;
42. end;
43.  

[Almir.Bispo]

You can use this.The CSV Comp DB with CSV-Pascal Library (open source).You  must prefer semi-colon delimited file
free get on http://adltecnologia.blogspot.com.br
Look PowerFul Exemple below

Code: Pascal  [Select][+][-]

1.  //ILDE-Pascal (open-source)
2. {$i ...\CQL_TO_PASCAL.txt}
3. procedure MycsvONDB;
4. var myresult:Tstringlist;
5.     cursor,db,id_table:string;
6. begin
7. myresult:=Tstrinlist.create;
8. db :='c:\mydb';
9. id_table :='MyTable'; //csv table
10. //add CQL Command to run
11. cursor :=  default_delimiter(db,id_table,',');//change ',' by default (';')  delimiter
12. cursor := set_underline(db,id_table);         //change space key by underline (no data lost)
13. //maybe ou need to list all data on column index 2 (or other)
14. cursor := field_list(db,id_table,'Any',2); //all data is listed on MyTable.que
15. CSV_COMP_DB_execute(cursor);//DB execution
16. //now just load result
17. while not ( fileexists('lock.inf') )do begin {wait start} end;
18. while  ( fileexists('lock.inf') ) do begin {wait execution} end;
19. //load
20. myresult.loadfromfile(application.location + id_table + '.que');
21. Memo1.text := myresult.text;
22. myresult.free;
23.  
24. end;
25.  

The exemple must  runs on same path of CSV Comp DB (Desktop version)
You can do Everthing with csv (Nosql Cloud technology,IOT,E-Commerce).
Everthing Free and Open