KEYWORDS: File copy AREA: General
Q: How do I copy a file?
A: Here are three ways:
{This way uses a File stream.}
Procedure FileCopy( Const sourcefilename, targetfilename: String );
Var
S, T: TFileStream;
Begin
S := TFileStream.Create( sourcefilename, fmOpenRead );
try
T := TFileStream.Create( targetfilename,
fmOpenWrite or fmCreate );
try
T.CopyFrom(S, S.Size ) ;
finally
T.Free;
end;
finally
S.Free;
end;
End;
{This way uses memory blocks for read/write.}
procedure FileCopy(const FromFile, ToFile: string);
var
FromF, ToF: file;
NumRead, NumWritten: Word;
Buf: array[1..2048] of Char;
begin
AssignFile(FromF, FromFile);
Reset(FromF, 1); { Record size = 1 }
AssignFile(ToF, ToFile); { Open output file }
Rewrite(ToF, 1); { Record size = 1 }
repeat
BlockRead(FromF, Buf, SizeOf(Buf), NumRead);
BlockWrite(ToF, Buf, NumRead, NumWritten);
until (NumRead = 0) or (NumWritten <> NumRead);
CloseFile(FromF);
CloseFile(ToF);
end;
{This one uses LZCopy, which USES LZExpand.}
procedure CopyFile(FromFileName, ToFileName: string);
var
FromFile, ToFile: File;
begin
AssignFile(FromFile, FromFileName); { Assign FromFile to FromFileName }
AssignFile(ToFile, ToFileName); { Assign ToFile to ToFileName }
Reset(FromFile); { Open file for input }
try
Rewrite(ToFile); { Create file for output }
try
{ copy the file an if a negative value is returned }
{ raise an exception }
if LZCopy(TFileRec(FromFile).Handle, TFileRec(ToFile).Handle) < 0
then
raise EInOutError.Create('Error using LZCopy')
finally
CloseFile(ToFile); { Close ToFile }
end;
finally
CloseFile(FromFile); { Close FromFile }
end;
end;