00302.txt

Delphi编程五大妙招源程序

//下面函数返回当前程序的目录
function GetCurrentPath :string;
begin
  Result:=ExtractFilePath(Application.Exename);
end;

//得到光驱
Function GetCDROM :String;
Var
  drv :DWORD;
  mask :BYTE;
  drive :String;
begin
  mask :=$80;
  drv :=GetLogicalDrives;
  Repeat
    if (drv and mask)<>0 then Break;
    mask :=mask shr 1;
  Until False;
  Repeat
  drv :=Trunc(log2(mask))+65;
  drive :=Chr(drv)+':';
  if GetDriveType(PChar(drive))=5 then Break;
  mask :=mask shr 1;
  until (mask=1);
  Result :=drive;
end;

//得到windows目录
function GetWindowsDir: String;
var
  ac: array [1..20] of Char;
  pc: PChar;
begin
  pc := @ac;
  GetWindowsDirectory(pc, 20);
  Result := pc;
end;

//得到System目录
function GetSystemDir: String;
var
  ac: array [1..20] of Char;
  pc: PChar;
begin
  pc := @ac;
  GetTempPath(20, pc); 
  Result := pc;
end;

//得到windows临时路径
function GetTempDir: String;
var
  ac: array [1..20] of Char;
  pc: PChar;
begin
  pc := @ac;
  GetSystemDirectory(pc, 20);
  Result := pc;
end;

//察看文件是否存在
FileExists(FileName:String):Boolean;

//改变文件扩展名
ChangeFileExt(FileName:String);

//得到文件的扩展名
ExtractFileExt(FileName:String):String;