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Posted on 2003-11-23
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Last Modified: 2011-08-18
I have this program so far - i need to return an error message if the file entered doesnt exist....

program Project1;

{$APPTYPE CONSOLE}

uses
  SysUtils;

var Input      : text;
      I          : integer;
      Lineoftext : string;
      S : string;

  Begin

  Readln (S);

  Reset(input,S);
  for I:=1 to 10 do begin
  Readln (Input,Lineoftext); {Reading a Lineoftext from input file}
  writeln (Lineoftext);
  end;
  Closefile (Input);
  readln;
  end.


Thanks :)

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Question by:jarhys
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6 Comments
 
LVL 9

Accepted Solution

by:
ginsonic earned 25 total points
ID: 9805867
Just use FileExists function as:

if not FileExists( S )  then begin
  ShowMessage( 'The file don't exist!' );
  Exit;
end;
0
 
LVL 8

Assisted Solution

by:gmayo
gmayo earned 25 total points
ID: 9805871
if FileExists(LineOfText) then begin
   ...file exists...
   ExitCode := 0;
end else begin
   ... file does not exist...
   ExitCode := 1; // or whatever
end;

It's in the SysUtils unit which you already include.

Geoff M.
0
 
LVL 4

Expert Comment

by:nestorua
ID: 9805931
HI,
You also can use "try..except..end" to catch the error.
Sincerely,
Nestorua.
0
 
LVL 5

Expert Comment

by:DeerBear
ID: 9810056
Hi,

Eventually you can also use FileStream, which would also allow for more
flexybility in your data processing.

HTH,

Andrew
0

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