一个写record类型到filestream的难题。

Question

我定义了一个类型：
type person=record
  a:integer;
  b:string;
  c:tjpegimage;
  d:tdatetime;
end;
现在程序中有一个该类型的实例P，我的问题是，如何将p利用filestream保存成一个二进制文件。
希望各位高人能指点指点！谢谢

Answer 1

用TFileStream的WriteBuffer函数。
fstrm:TFileStream;
fstrm.WriteBuffer(@P,sizeof(p));

Answer 2

unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;type
  person=record
    a:integer;
    b:string;
    c:Double;
    d:tdatetime;
  end;  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);//保存
var
  s:TFileStream;
  p:Person;
begin
  p.a:=10;
  p.b:='test';
  p.c:=12.34567;
  p.d:=StrtoDateTime('2002-01-01');  s:=TFileStream.Create('c:\t.bin',fmOpenReadWrite or fmCreate);
  try
    s.Write(p,Sizeof(Person));
  finally
    s.Free;
  end;
end;procedure TForm1.Button2Click(Sender: TObject);//读取
var
  s:TFileStream;
  p:Person;
begin
  s:=TFileStream.Create('c:\t.bin',fmOpenRead);
  try
    s.Read(p,Sizeof(Person));
  finally
    s.Free;
  end;
  ShowMessage('如果显示的数据和保存过程中的数据一样，说明FileStream保存成功'#13+
              IntToStr(p.a)+#13+
              p.b+#13+
              FloatToStr(p.c)+#13+
              FormatDateTime('yyyy-mm-dd',p.d));
end;end.

Answer 3

贴一段代码给你,你改改吧
unit ceshi;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;type
  TForm1 = class(TForm)
    Button1: TButton;
    OpenDialog1: TOpenDialog;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);  private
    { Private declarations }
  public
    { Public declarations }
  end;
type
//枚举
mymj=(a,b,c,d,e);
//集合
myjh=set of mymj;
//静态数组
mysz=array[1..10] of integer;
//子界
myzj='a'..'z';
//记录
myrecord=record
         name:array[1..10] of char;
         age:0..200;
         sex:(gril,boy);
         filed1:mymj;
         filed2:myjh;
         filed3:mysz;
         filed4:myzj;
         case tag:boolean of
              true:(filed5:integer;);
              false:(filed6:string[100]);
         end;
//文件
myfile=file of myrecord;
myfile_nottype=file;
var
  Form1: TForm1;
  tmymj:mymj;
  tmyjh:myjh;
  tmysz:mysz;
  tmyzj:myzj;
  tmyrecord:myrecord;
  tmyfile:myfile;
  tmyfile_nottype:myfile_nottype;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);
varFileName:string;begin
tmyjh:=[a,c,e];
tmysz[1]:=1982;
tmysz[2]:=3;
tmysz[3]:=20;
if tmymj=a then  showmessage('符合条件《枚举》');
if a in tmyjh then  showmessage('符合条件《集合》');
if tmysz[3]= 20 then  showmessage('符合条件《数组》');tmyrecord.name :='wangyuntao';
tmyrecord.age :=22;
tmyrecord.sex :=boy;
tmyrecord.filed1 :=a;
tmyrecord.filed2 :=[a,b,c];
tmyrecord.filed3[1]:=100;
tmyrecord.filed4 :='h';
tmyrecord.tag :=true;
tmyrecord.filed5 :=99;
tmyrecord.filed6 :='ok';if OpenDialog1.Execute then
FileName := OpenDialog1.FileName
else exit;AssignFile(tmyfile,Filename);
Reset(tmyfile);
//Write(tmyfile,tmyrecord);
read(tmyfile,tmyrecord) ;
showmessage(tmyrecord.name );
showmessage(inttostr(tmyrecord.age));
//子界
showmessage(tmyrecord.filed4);end;
procedure TForm1.Button2Click(Sender: TObject);
var
i:pointer;
pi:pinteger;
ki:pstring;
ps:single;
ka:ansistring;begin
ps:=25869;
ka:='i love delphi!';
//取PS地址->I:POINTER
i:=@ps;
//将I强制转换成pi:pinteger
pi:=pinteger(i);
SHOWMESSAGE(INTTOSTR(PI^)) ;//取KA地址
i:=@ka;
ki:=pstring(i);
showmessage(ki^);
end;end.