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A relative pathname in delphi

Posted on 2008-06-20
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Last Modified: 2012-05-05
I need to adress the file '/data/1.txt' relative to the application. What is the syntax?
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Question by:Sunsales
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8 Comments
 
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Accepted Solution

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arioh earned 250 total points
ID: 21829847
try ".\data\1.txt"
or ExtractFilePath( ParamStr( 0 ) ) + "\data\1.txt"
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Expert Comment

by:Geert Gruwez
ID: 21830028
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




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LVL 17

Expert Comment

by:TheRealLoki
ID: 21830734
actually, arioh is nearly right
it's
ExtractFilePath( ParamStr( 0 ) ) + 'data\1.txt'

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LVL 2

Expert Comment

by:Ustin19
ID: 21837163
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
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Author Comment

by:Sunsales
ID: 21838687
Ustin, a question - does the line:
  BlockRead(F,Result[1],FSz);

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

by:Sunsales
ID: 21842129
Thanx for additional answer.
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LVL 2

Expert Comment

by:Ustin19
ID: 21853842
yes, string with whole file will be returned.
It is example only :) but for 80mb it is possible
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LVL 2

Expert Comment

by:Ustin19
ID: 21853850
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
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