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问题来源: http://www.cnblogs.com/del/archive/2010/04/21/1717584.html#1809298

//方法 1: 共用内存
procedure TForm1.Button1Click(Sender: TObject);
var
  bf: record b1,b2,b3,b4: Byte end;
  i: Integer absolute bf;
begin
  bf.b1 := $CC;
  bf.b2 := $DD;
  bf.b3 := $EE;
  bf.b4 := $FF;
  ShowMessageFmt('%x', [i]); //FFEEDDCC
end;

//方法 2: 位运算
procedure TForm1.Button2Click(Sender: TObject);
var
  i: Integer;
begin
  i := $CC or ($DD shl 8) or ($EE shl 16) or ($FF shl 24); //不用括号也可
  ShowMessageFmt('%x', [i]); //FFEEDDCC
end;

//方法 3: 使用函数
procedure TForm1.Button3Click(Sender: TObject);
var
  i: Integer;
begin
  i := MakeLong(MakeWord($CC,$DD), MakeWord($EE,$FF));
  ShowMessageFmt('%x', [i]); //FFEEDDCC
end;

//方法 4: 从静态数组...
procedure TForm1.Button4Click(Sender: TObject);
var
  bs: array[0..3] of Byte;
  P: PInteger;
begin
  bs[0] := $CC;
  bs[1] := $DD;
  bs[2] := $EE;
  bs[3] := $FF;
  P := @bs;
  ShowMessageFmt('%x', [P^]); //FFEEDDCC
end;

//方法 5: 从动态数组...
procedure TForm1.Button5Click(Sender: TObject);
var
  bs: array of Byte;
  P: PInteger;
begin
  SetLength(bs, 4);
  bs[0] := $CC;
  bs[1] := $DD;
  bs[2] := $EE;
  bs[3] := $FF;
  P := @bs[0];
  ShowMessageFmt('%x', [P^]); //FFEEDDCC
end;

posted on 2010-04-24 16:13  万一  阅读(...)  评论(...编辑  收藏