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How to pass FileName as a string?

Posted on 2004-09-18
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Last Modified: 2010-04-05
O.K., I have been stuck on this for about 3 days straight.  I am trying to pass the name of a file as a string so I can open it in a procedure.  The problem I am having, is that TStringList is not compatible with String (obvious, I know).  Here's some of my code:

//Onclick procedure which lets the user navigate to and select a file.

procedure TForm1.Button1Click(Sender: TObject);

var
  OpenFile : TOpenDialog;
  FileName : TStringList;

begin

  OpenFile := TOpenDialog.Create(self);
  OpenFile.InitialDir := GetCurrentDir;
  OpenFile.Options := [ofFileMustExist];
  OpenFile.Filter := 'CSV files only |*.csv';
  OpenFile.FilterIndex := 2;

   if OpenFile.Execute
     then FileName := Tstringlist.Create
         else MessageDlg('Are you sure?',mtError, mbOKCancel, 0);

   Edit1.Text := OpenFile.FileName;

end;

//Here's the procedure which loads the CSV and stores the data in an array.


Procedure CSVimport(FileName: String);
Var
  MyFile, MyColumns: TStringList;
  Row, Col: integer;
begin
 
  MyFile := TStringList.Create;
  MyColumns := TStringList.Create;
  MyColumns.QuoteChar := ' ';
  try
    MyFile.LoadFromFile(FileName);  //This is where the code errors.  File name is not passed.
    If MyFile.Count > 0 then
    Begin
      MyColumns.DelimitedText := MyFile[Row];

      For Col := 0 to MyColumns.Count -1 Do
        MyColumns[Col] := MyColumns[Col] + ' varchar(50)';

      MyFile[Row] := 'CREATE TABLE TABLE1 (ID INT(2), ' + MyColumns.DelimitedText +  ', PRIMARY KEY(ID));';
    end;  

This is not all the code, the rest seems to compile no probs.  I just can't figure out how pass the file name to the procedure, so I can load it in the procedure and pass the contents of the CSV into the array.  I realize there are a few ways of doing this, however, my main goal is to pass the filename as a string, so I can potentially use a constructor Create(FileName: String); in another unit.  I can figure this part out, just need to get through my initial stumbling block...  

HELP!!

Ta.
0
Comment
Question by:south_paw
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4 Comments
 
LVL 2

Expert Comment

by:gary_williams
ID: 12093486

Why do you not call

CSVImport(OpenFile.FileName);

instead of stuffing the filename into an edit control?
0
 
LVL 4

Accepted Solution

by:
Evarest earned 2000 total points
ID: 12093490
I'm at a loss :-)

Your code as you give it gives no error with me. Its syntax is correct.

If you want to pass the FileName as string to a procedure, and that filename is stored in a TStringList, just pass an item out of that list to the procedure. I've altered your code so that every file opened by using TOpenDialog will be sent to the CSVImport procedure:

procedure TForm1.Button1Click(Sender: TObject);
var
  OpenFile : TOpenDialog;
  FileName : TStringList;
  Q: integer;
begin

  OpenFile := TOpenDialog.Create(self);
  OpenFile.InitialDir := GetCurrentDir;
  OpenFile.Options := [ofFileMustExist, ofAllowMultiSelect]; //<-- ofAllowMultiSelect to select more files in the TOpenDialog
  OpenFile.Filter := 'CSV files only |*.csv';
  OpenFile.FilterIndex := 2;

   if OpenFile.Execute
    then
     begin
      for Q :=0 to OpenFile.Files.Count -1 do // <-- Loop to send the FileNames to the procedure
       begin
        CSVImport(OpenFile.Files[Q]); // <-- Call to the procedure CSVImport
       end;
     end
     else MessageDlg('Are you sure?',mtError, mbOKCancel, 0);

   // Edit1.Text := OpenFile.FileName; // <-- has no use when multiselecting

end;

//Here's the procedure which loads the CSV and stores the data in an array.


Procedure CSVimport(FileName: String);
Var
  MyFile, MyColumns: TStringList;
  Row, Col: integer;
begin
 
  MyFile := TStringList.Create;
  MyColumns := TStringList.Create;
  MyColumns.QuoteChar := ' ';
  try
    MyFile.LoadFromFile(FileName);  //This is where the code errors.  File name is not passed.
    If MyFile.Count > 0 then
    Begin
      MyColumns.DelimitedText := MyFile[Row];

      For Col := 0 to MyColumns.Count -1 Do
        MyColumns[Col] := MyColumns[Col] + ' varchar(50)';

      MyFile[Row] := 'CREATE TABLE TABLE1 (ID INT(2), ' + MyColumns.DelimitedText +  ', PRIMARY KEY(ID));';
    end;
  except
  end;
end;

Let me know if this is what you mean!
Evarest
0
 
LVL 7

Expert Comment

by:LRHGuy
ID: 12093493
Maybe I don't understand the problem, but why don't you make Filename a string, as in:

procedure TForm1.Button1Click(Sender: TObject);

var
  OpenFile : TOpenDialog;
  FileName : String;

begin

  OpenFile := TOpenDialog.Create(self);
  OpenFile.InitialDir := GetCurrentDir;
  OpenFile.Options := [ofFileMustExist];
  OpenFile.Filter := 'CSV files only |*.csv';
  OpenFile.FilterIndex := 2;

   if OpenFile.Execute
     then begin
        FileName := OpenFile.FileName;

       CVSImport(FileName);
    end
    else
      MessageDlg('Are you sure?',mtError, mbOKCancel, 0);

   Edit1.Text := OpenFile.FileName;

end;
0
 

Author Comment

by:south_paw
ID: 12093586
Thanks, I get it now.
0

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