asked on

A relative pathname in delphi

I need to adress the file '/data/1.txt' relative to the application. What is the syntax?

ASKER CERTIFIED SOLUTION

arioh

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

Geert G

the first \ indicates the file is at the root of drive
if you use ".\data\1.txt" you will start from GetCurrentDir

use
FileName := IncludeTrailingPathDelimiter(ExtractFilePath( ParamStr( 0 ) )) + "data\1.txt";
as arioh suggested

TheRealLoki

actually, arioh is nearly right
it's
ExtractFilePath( ParamStr( 0 ) ) + 'data\1.txt'

Ustin19

CreateFile or OpenFile (AssignFile etc is wrappers for it under windows) uses current directory of application (at start it is usually is folder with exe until You call SetCurrentDirectory) to adressing with relative pathes. So, code
Function FileToString(FileName:String):String;
Var F:File of Char;
Fsz:Integer;
Begin
Result:='';
If FileExists(FileName) then
Begin
AssignFile(F,FileName);
Reset(F);
Fsz:=FileSize(F);
SetString(Result,Nil,Fsz);
BlockRead(F,Result[1],FSz);
CloseFile(F);
End;//If
End;//FileToString
calling as
FileToString('data\1.txt') returns string with content of exe-relative located \data\1.txt

Paer Toernell

ASKER

Ustin, a question - does the line:
BlockRead(F,Result[1],FSz);

read the whole file? I have 80 mb files....

Paer Toernell

ASKER

Thanx for additional answer.

Ustin19

yes, string with whole file will be returned.
It is example only :) but for 80mb it is possible

Ustin19

and this way is theoretically applicable for less than 2GB files, but for this it is VERY slow and it is danger to obtain EOutOfMemory exception