delphi 编程 获得同相应扩展文件名关联的应用程序，代码 如下：
unit Unit1;
interface
uses
Windows, Messages, Registry,IniFiles,SysUtils, Variants, Classes, Graphics, Controls, Form s,
Dialogs, StdCtrls;
type
TForm 1 = class(TForm )
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form 1: TForm 1;
implementation
{$R *.dfm}
function GetProgramAssociation (Ext : string) : string;
//取得相关联的文件
var
reg: TRegistry;
s : string;
WinIni : TIniFile;
WinIniFileName : array[0..MAX_PATH] of char;
begin
s := ‘‘;
reg := TRegistry.Create;
//生成注册表对象
reg.RootKey := HKEY_CLASSES_ROOT;
if reg.OpenKey(‘.‘ + ext + ‘\shell\open\command‘,false) <> false then
//打开指定的键值
begin
s := reg.ReadString(‘‘);
reg.CloseKey;
end
else
begin
//如果不能打开
if reg.OpenKey(‘.‘ + ext, false) <> false then
begin
s := reg.ReadString(‘‘);
reg.CloseKey;
if s <> ‘‘ then
begin
if reg.OpenKey(s + ‘\shell\open\command‘,false) <> false then
s := reg.ReadString(‘‘);
reg.CloseKey;
end;
end;
end;
if Pos(‘%‘, s) > 0 then
Delete(s, Pos(‘%‘, s), length(s));
if ((length(s) > 0) and (s[1] = ‘"‘)) then
Delete(s, 1, 1);
if ((length(s) > 0) and (s[length(s)] = ‘"‘)) then
Delete(s, Length(s), 1);
while ((length(s) > 0) and ((s[length(s)] = #32) or
(s[length(s)] = ‘"‘))) do
Delete(s, Length(s), 1);
GetWindowsDirectory(WinIniFileName, sizeof(WinIniFileName));
//得到系统目录
StrCat(WinIniFileName, ‘\win.ini‘);
WinIni := TIniFile.Create(WinIniFileName);
s := WinIni.ReadString(‘Extensions‘,ext,‘‘);
WinIni.Free;
{Delete any command line}
if Pos(‘ ^‘, s) > 0 then
Delete(s, Pos(‘ ^‘, s), length(s));
result := s;
end;
procedure TForm 1.Button1Click(Sender: TObject);
begin
ShowMessage(GetProgramAssociation(‘gif‘));
end;
end.