发送文件是否是将文件写入流中进行发送？ ( 积分: 100 )

如果是。怎样将文件写如流中。代码是什么？

如果是。怎样将文件写如流中。代码是什么？

AFileStream:=TFileStream.Create(FileName,fmOpenRead);//创建打开一个文件流
index:=0
AFileStream.Seek(index,soBeginning);将指针移到文件开始;
MyStream.clear;
MyStream.CopyFrom(AFileStream,AFileStream.Size);//写入流
.....
MyStream.Position:=0;

procedure TForm1.Save1Click(Sender: TObject);

var
NewFileName: string;
Msg: string;
NewFile: TFileStream;
OldFile: TFileStream;
begin
NewFileName := ExtractFilePath(Application.ExeName) + ExtractFileName(Edit1.Text);
Msg := Format('Copy %s to %s?', [Edit1.Text, NewFileName]);
if MessageDlg(Msg, mtCustom, mbOKCancel, 0) = mrOK then
begin
OldFile := TFileStream.Create(Edit1.Text, fmOpenRead or fmShareDenyWrite);
try
NewFile := TFileStream.Create(NewFileName, fmCreate or fmShareDenyRead);

try
NewFile.CopyFrom(OldFile, OldFile.Size);
finally
FreeAndNil(NewFile);
end;
finally
FreeAndNil(OldFile);
end;
end;

end;

部分代码仅供参考：
unit DTPClient;

interface
uses
CommClient, Classes;

const
DEFAULT_TTL = 86400*30*3; //缺省生存周期
DEFAULT_PATH= './Received_Files'; //指定目录无法创建时, 文件保存位置

type
//数据包头
TDTPPacket = packed record
Source : String; //源地址
Destination : String; //目标地址
Command : String; //命令码
Data : String; //数据
Context : String; //附加参数
FileName : String; //如果不为空表示还需要发送文件
Memo : String; //备注字段
end;

//数据包到达通知事件
TDTPDataEvent = procedure (Sender: TObject; aDTPPacket: TDTPPacket; out aAction: Integer) of object;

//数据传送客户端
TDTPClient = class(TCommClient)
private
FOnDTPData : TDTPDataEvent;

function ReadStringFromStream(aStream: TStream): String;
procedure WriteStringToStream(aStream: TStream; const aString: String);

protected
procedure setOnData(aValue: TOnDataEvent); override; //
procedure OnRecv(Sender: TObject; aData: TStream; const aSource: String; out aAction: Integer);

public
constructor Create(aOwner: TComponent); override;

function SendData(const aDTPPacket: TDTPPacket; aTTL: Integer=DEFAULT_TTL): Integer;

published
property OnDTPData: TDTPDataEvent read FOnDTPData write FOnDTPData;
end;

procedure Register;

implementation
uses
SysUtils, LogFiles, Windows;

procedure Register;
begin
RegisterComponents('Samples', [TDTPClient]);
end;

constructor TDTPClient.Create(aOwner: TComponent);
begin
inherited Create(aOwner);
OnData := OnRecv;
end;

function TDTPClient.SendData(const aDTPPacket: TDTPPacket; aTTL: Integer=DEFAULT_TTL): Integer;
var
Stream : TMemoryStream;
aFile : TFileStream;
FileSize: Integer;
Packet : TDTPPacket;
begin
Result := -1;

Packet := aDTPPacket;

//文件不存在
if not FileExists(Packet.FileName) then Packet.FileName := '';

Stream := TMemoryStream.Create;
try
try
//将包头写入流中
Stream.Seek(0, soFromBeginning);
with Packet do
begin
// WriteStringToStream(Stream, Source); 源地址不发送, 自动添加
WriteStringToStream(Stream, Destination);
WriteStringToStream(Stream, Command);
WriteStringToStream(Stream, Data);
WriteStringToStream(Stream, Context);
WriteStringToStream(Stream, FileName);
WriteStringToStream(Stream, Memo);
end;

//如果需要发送文件, 将文件写入流中
if Trim(Packet.FileName) <> '' then
try
aFile := TFileStream.Create(Packet.FileName, fmOpenRead);
try
FileSize := aFile.Size;
aFile.Seek(0, soFromBeginning);
Stream.Write(FileSize, SizeOf(FileSize)); //将文件尺寸写入流中
Stream.CopyFrom(aFile, FileSize); //将文件内容写入流中
finally
aFile.Free;
end;
except
on E: Exception do
begin
TLogFile.WriteLn('读取需要发送的文件失败, 错误信息="%s"', [E.Message]);
end;
end;

//发送
Result := Send(Stream, aDTPPacket.Destination, aTTL);
except
//发送失败
on E: Exception do
begin
TLogFile.WriteLn('数据发送失败, 错误信息="%s"', [E.Message]);
end;
end;
finally
Stream.Free;
end;
end;

procedure TDTPClient.setOnData(aValue: TOnDataEvent);
begin
inherited setOnData(OnRecv);
end;

function TDTPClient.ReadStringFromStream(aStream: TStream): String;
var
Len : Integer;
Str : String;
begin
try
Str := '';

aStream.Read(Len, SizeOf(Len)); //从流中读入字符串长度
if Len > 0 then
begin
SetLength(Str, Len);
aStream.Read(Str[1], Len); //从流中读入字符串
end;
except
on E: Exception do
begin
Str := '';
end;
end;

Result := Str;
end;

procedure TDTPClient.WriteStringToStream(aStream: TStream; const aString: String);
var
Len : Integer;
begin
Len := Length

AFileStream:=TFileStream.Create('c:/1.exe',fmOpenRead)
AFileStream.Seek(0,soBeginning);将指针移到文件开始;
MyStream.clear;
MyStream.CopyFrom(AFileStream,AFileStream.Size)

mystream到底能存多大的文件，怎么一百多兆就不行了。？

怎么一百多兆就不行了。？ 太大了吧!!!
index:=0
BufferLeb:=32000;
Repeat
AFileStream.Seek(index,soBeginning);将指针移到文件开始;
MyStream.clear;
MyStream.CopyFrom(AFileStream,BufferLen);//写入流
.....
MyStream.Position:=0;
....
Index:=Index+BufferLen;
Until Index<AFileStream.Size;