文件管理

一 读出文件的长度

var

f: file of Byte;

size : Longint;

begin

AssignFile(f, f:\t.exe);

Reset(f);

size := FileSize(f);

edit1.text := IntToStr(size);

CloseFile(f);

end;

或:

var

fh:integer;

fs:longint;

begin

fh:=fileopen(文件名,fmopenread);

fs:=fileseek(fh,0,2);

fileclose(fh);

end;

二 将字符串用二进制模式写入文件

var

filehandle:integer;

filename:string;

fn:string;

begin

filehandle:=fileopen(filename,fmopenreadwrite);

fileseek(filehandle,i*256,0);

getmem(buffer,300);

try

strpcopy(buffer,fn);

filewrite(filehandle,buffer^,256);

finally

freemem(buffer);

end;

fileclose(filehandle);

end;

三 使用readln()从文件中读出超过255字符的字串

Type

{use longest line you may encounter here}

TLine = Array [0..1024] of Char;

PLine = ^TLine;

Var

pBuf: PLine;

...

New( pBuf );

...

ReadLn( F, pBuf^ );

四 向文本文件后追加一行

var

filevar: textfile;

buf:string;

begin

assignfile(filevar,txt.log);

append(filevar);

writeln(filevar,buf);

closefile(filevar);

end;