delphi 数据快照内存泄漏
delphi datasnap memory leak
我正在制作 Datasnap 客户端和服务器应用程序的原型。我想将文件从服务器流式传输到客户端。
这是有效的，但我流式传输的每个文件都保留在服务器的内存中。它永远不会被释放，即使我关闭连接/客户端也不会。
我尝试使用：GetInvocationMetaData.CloseSession := True;
在服务器上的方法调用中，但后来我没有得到文件，它是 0 Kb。
我做错了什么？
服务器端代码：（请原谅我的命名）
生命周期是调用
unit ServerMethodsUnitNKDataSnap;
interface
uses System.SysUtils, System.Classes, Datasnap.DSServer, Datasnap.DSAuth,
Data.DB, IBCustomDataSet, IBQuery, IBDatabase, Datasnap.Provider, DataSnap.DSSession, Data.DBXPlatform;
type
TServerMethods1 = class(TDSServerModule)
private
// FStream:TStream;
public
{ Public declarations }
function EchoString(Value: string): string;
function ReverseString(Value: string): string;
function DownloadFile(sFile:String): TStream;
function BestaatFile(sFile:String):Boolean;
procedure FreeStream;
end;
implementation
{$R *.dfm}
uses System.StrUtils;
function TServerMethods1.EchoString(Value: string): string;
begin
Result := Value;
end;
procedure TServerMethods1.FreeStream;
begin
// FreeAndNil(FStream);
GetInvocationMetaData.CloseSession := True;
end;
function TServerMethods1.ReverseString(Value: string): string;
begin
Result := System.StrUtils.ReverseString(Value);
GetInvocationMetaData.CloseSession := True;
end;
function TServerMethods1.DownloadFile(sFile:String): TStream;
begin
{
if Assigned(FStream) then
FreeAndNil(FStream);
FStream := TFileStream.Create(sFile, fmOpenRead or fmShareDenyNone);
Result := FStream;
TFileStream(Result).Seek(0, TSeekOrigin.soBeginning);
}
result := TFileStream.Create(sFile, fmOpenRead or fmShareDenyNone);
TFileStream(Result).Seek(0, TSeekOrigin.soBeginning);
// GetInvocationMetaData.CloseSession := True;
end;
function TServerMethods1.BestaatFile(sFile: string):Boolean;
begin
Result := FileExists(sFile);
GetInvocationMetaData.CloseSession := True;
end;
end.
dfm
object ServerContainer2: TServerContainer2
OldCreateOrder = False
Height = 271
Width = 415
object DSServer1: TDSServer
Left = 96
Top = 11
end
object DSHTTPService1: TDSHTTPService
HttpPort = 7070
Server = DSServer1
Filters = <>
Left = 96
Top = 135
end
object DSServerClass1: TDSServerClass
OnGetClass = DSServerClass1GetClass
Server = DSServer1
LifeCycle = 'Invocation'
Left = 200
Top = 11
end
end
客户端代码
生成源
//
// Created by the DataSnap proxy generator.
// 2-2-2015 14:27:21
//
unit ClientClassesUnit1;
interface
uses Datasnap.DSProxyRest, Datasnap.DSClientRest, Data.DBXCommon, Data.DBXClient, Data.DBXDataSnap, Data.DBXJSON, Datasnap.DSProxy, System.Classes, System.SysUtils, Data.DB, Data.SqlExpr, Data.DBXDBReaders, Data.DBXCDSReaders, Data.DBXJSONReflect;
type
TServerMethods1Client = class(TDSAdminRestClient)
private
FEchoStringCommand: TDSRestCommand;
FReverseStringCommand: TDSRestCommand;
FDownloadFileCommand: TDSRestCommand;
FDownloadFileCommand_Cache: TDSRestCommand;
FBestaatFileCommand: TDSRestCommand;
FFreeStreamCommand: TDSRestCommand;
public
constructor Create(ARestConnection: TDSRestConnection); overload;
constructor Create(ARestConnection: TDSRestConnection; AInstanceOwner: Boolean); overload;
destructor Destroy; override;
function EchoString(Value: string; const ARequestFilter: string = ''): string;
function ReverseString(Value: string; const ARequestFilter: string = ''): string;
function DownloadFile(sFile: string; const ARequestFilter: string = ''): TStream;
function DownloadFile_Cache(sFile: string; const ARequestFilter: string = ''): IDSRestCachedStream;
function BestaatFile(sFile: string; const ARequestFilter: string = ''): Boolean;
procedure FreeStream;
end;
const
TServerMethods1_EchoString: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'Value'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 26; TypeName: 'string')
);
TServerMethods1_ReverseString: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'Value'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 26; TypeName: 'string')
);
TServerMethods1_DownloadFile: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'sFile'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 33; TypeName: 'TStream')
);
TServerMethods1_DownloadFile_Cache: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'sFile'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 26; TypeName: 'String')
);
TServerMethods1_BestaatFile: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'sFile'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 4; TypeName: 'Boolean')
);
implementation
function TServerMethods1Client.EchoString(Value: string; const ARequestFilter: string): string;
begin
if FEchoStringCommand = nil then
begin
FEchoStringCommand := FConnection.CreateCommand;
FEchoStringCommand.RequestType := 'GET';
FEchoStringCommand.Text := 'TServerMethods1.EchoString';
FEchoStringCommand.Prepare(TServerMethods1_EchoString);
end;
FEchoStringCommand.Parameters[0].Value.SetWideString(Value);
FEchoStringCommand.Execute(ARequestFilter);
Result := FEchoStringCommand.Parameters[1].Value.GetWideString;
end;
function TServerMethods1Client.ReverseString(Value: string; const ARequestFilter: string): string;
begin
if FReverseStringCommand = nil then
begin
FReverseStringCommand := FConnection.CreateCommand;
FReverseStringCommand.RequestType := 'GET';
FReverseStringCommand.Text := 'TServerMethods1.ReverseString';
FReverseStringCommand.Prepare(TServerMethods1_ReverseString);
end;
FReverseStringCommand.Parameters[0].Value.SetWideString(Value);
FReverseStringCommand.Execute(ARequestFilter);
Result := FReverseStringCommand.Parameters[1].Value.GetWideString;
end;
function TServerMethods1Client.DownloadFile(sFile: string; const ARequestFilter: string): TStream;
begin
if FDownloadFileCommand = nil then
begin
FDownloadFileCommand := FConnection.CreateCommand;
FDownloadFileCommand.RequestType := 'GET';
FDownloadFileCommand.Text := 'TServerMethods1.DownloadFile';
FDownloadFileCommand.Prepare(TServerMethods1_DownloadFile);
end;
FDownloadFileCommand.Parameters[0].Value.SetWideString(sFile);
FDownloadFileCommand.Execute(ARequestFilter);
Result := FDownloadFileCommand.Parameters[1].Value.GetStream(FInstanceOwner);
end;
function TServerMethods1Client.DownloadFile_Cache(sFile: string; const ARequestFilter: string): IDSRestCachedStream;
begin
if FDownloadFileCommand_Cache = nil then
begin
FDownloadFileCommand_Cache := FConnection.CreateCommand;
FDownloadFileCommand_Cache.RequestType := 'GET';
FDownloadFileCommand_Cache.Text := 'TServerMethods1.DownloadFile';
FDownloadFileCommand_Cache.Prepare(TServerMethods1_DownloadFile_Cache);
end;
FDownloadFileCommand_Cache.Parameters[0].Value.SetWideString(sFile);
FDownloadFileCommand_Cache.ExecuteCache(ARequestFilter);
Result := TDSRestCachedStream.Create(FDownloadFileCommand_Cache.Parameters[1].Value.GetString);
end;
function TServerMethods1Client.BestaatFile(sFile: string; const ARequestFilter: string): Boolean;
begin
if FBestaatFileCommand = nil then
begin
FBestaatFileCommand := FConnection.CreateCommand;
FBestaatFileCommand.RequestType := 'GET';
FBestaatFileCommand.Text := 'TServerMethods1.BestaatFile';
FBestaatFileCommand.Prepare(TServerMethods1_BestaatFile);
end;
FBestaatFileCommand.Parameters[0].Value.SetWideString(sFile);
FBestaatFileCommand.Execute(ARequestFilter);
Result := FBestaatFileCommand.Parameters[1].Value.GetBoolean;
end;
procedure TServerMethods1Client.FreeStream;
begin
if FFreeStreamCommand = nil then
begin
FFreeStreamCommand := FConnection.CreateCommand;
FFreeStreamCommand.RequestType := 'GET';
FFreeStreamCommand.Text := 'TServerMethods1.FreeStream';
end;
FFreeStreamCommand.Execute;
end;
constructor TServerMethods1Client.Create(ARestConnection: TDSRestConnection);
begin
inherited Create(ARestConnection);
end;
constructor TServerMethods1Client.Create(ARestConnection: TDSRestConnection; AInstanceOwner: Boolean);
begin
inherited Create(ARestConnection, AInstanceOwner);
end;
destructor TServerMethods1Client.Destroy;
begin
FEchoStringCommand.DisposeOf;
FReverseStringCommand.DisposeOf;
FDownloadFileCommand.DisposeOf;
FDownloadFileCommand_Cache.DisposeOf;
FBestaatFileCommand.DisposeOf;
FFreeStreamCommand.DisposeOf;
inherited;
end;
end.
自己的来源
unit Unit1;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls,
Vcl.Grids, Vcl.DBGrids, IPPeerClient, Datasnap.DSClientRest;
type
TForm1 = class(TForm)
Button1: TButton;
Edit1: TEdit;
Label4: TLabel;
Button5: TButton;
Edit5: TEdit;
Label5: TLabel;
Edit6: TEdit;
Label6: TLabel;
DSRestConnection1: TDSRestConnection;
procedure Button1Click(Sender: TObject);
procedure Button5Click(Sender: TObject);
private
procedure DownloadFile(sSourceFile,sTargetFile:string);
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
uses ClientClassesUnit1;
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
var oServerMethodsClient:TServerMethods1Client;
begin
oServerMethodsClient := nil;
try
try
oServerMethodsClient := TServerMethods1Client.Create(DSRestConnection1, True);
ShowMessage(oServerMethodsClient.EchoString(edit1.Text));
ShowMessage(oServerMethodsClient.ReverseString(edit1.Text));
except
on E: Exception do
begin
showmessage('Oeps echo: ' + E.Message);
end;
end;
finally
FreeAndNil(oServerMethodsClient);
end;
end;
procedure TForm1.Button5Click(Sender: TObject);
begin
DownloadFile(edit5.Text, edit6.Text);
end;
procedure TForm1.DownloadFile(sSourceFile,sTargetFile:String);
var
RetStream: TStream;
fs:TFileStream;
oServerMethodsClient:TServerMethods1Client;
begin
oServerMethodsClient := nil;
RetStream := nil;
try
try
oServerMethodsClient := TServerMethods1Client.Create(DSRestConnection1, True);
RetStream := oServerMethodsClient.DownloadFile(sSourceFile);
// oServerMethodsClient.FreeStream;
fs := TFileStream.Create(sTargetFile, fmCreate);
try
if RetStream.Size > 0 then
begin
RetStream.Position:=0;
fs.CopyFrom(RetStream, RetStream.Size);
end;
finally
fs.free;
// retstream.Free;
end;
except
on E: Exception do
begin
showmessage('Oeps download: ' + E.Message);
end;
end;
finally
FreeAndNil(oServerMethodsClient);
end;
end;
end.
dfm 来源
object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 519
ClientWidth = 959
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
PixelsPerInch = 96
TextHeight = 13
object Label4: TLabel
Left = 208
Top = 48
Width = 53
Height = 13
Caption = 'Echo string'
end
object Label5: TLabel
Left = 208
Top = 93
Width = 22
Height = 13
Caption = 'van:'
end
object Label6: TLabel
Left = 208
Top = 123
Width = 22
Height = 13
Caption = 'naar'
end
object Button1: TButton
Left = 16
Top = 43
Width = 75
Height = 25
Caption = 'echo'
TabOrder = 0
OnClick = Button1Click
end
object Edit1: TEdit
Left = 288
Top = 45
Width = 274
Height = 21
TabOrder = 1
Text = 'bla'
end
object Button5: TButton
Left = 16
Top = 88
Width = 75
Height = 25
Caption = 'haal 1 file'
TabOrder = 2
OnClick = Button5Click
end
object Edit5: TEdit
Left = 288
Top = 93
Width = 274
Height = 21
TabOrder = 3
Text = 'c:\source\temp.zip'
end
object Edit6: TEdit
Left = 288
Top = 120
Width = 274
Height = 21
TabOrder = 4
Text = 'c:\temp\temp.zip'
end
object DSRestConnection1: TDSRestConnection
Host = 'localhost'
Port = 7070
LoginPrompt = False
PreserveSessionID = False
Left = 120
Top = 16
UniqueId = '{B4909821-9EF2-42F1-AFFF-58B320C35F75}'
end
end
DataSnap 服务器方法不正确支持 TStream。支持的类型列表可以在 docwiki 中找到：
Exposing DataSnap Server Methods
在你的情况下使用 TDBXStreamValue 似乎是合适的。
我正在制作 Datasnap 客户端和服务器应用程序的原型。我想将文件从服务器流式传输到客户端。
这是有效的，但我流式传输的每个文件都保留在服务器的内存中。它永远不会被释放，即使我关闭连接/客户端也不会。
我尝试使用：GetInvocationMetaData.CloseSession := True;
在服务器上的方法调用中，但后来我没有得到文件，它是 0 Kb。
我做错了什么？
服务器端代码：（请原谅我的命名） 生命周期是调用
unit ServerMethodsUnitNKDataSnap;
interface
uses System.SysUtils, System.Classes, Datasnap.DSServer, Datasnap.DSAuth,
Data.DB, IBCustomDataSet, IBQuery, IBDatabase, Datasnap.Provider, DataSnap.DSSession, Data.DBXPlatform;
type
TServerMethods1 = class(TDSServerModule)
private
// FStream:TStream;
public
{ Public declarations }
function EchoString(Value: string): string;
function ReverseString(Value: string): string;
function DownloadFile(sFile:String): TStream;
function BestaatFile(sFile:String):Boolean;
procedure FreeStream;
end;
implementation
{$R *.dfm}
uses System.StrUtils;
function TServerMethods1.EchoString(Value: string): string;
begin
Result := Value;
end;
procedure TServerMethods1.FreeStream;
begin
// FreeAndNil(FStream);
GetInvocationMetaData.CloseSession := True;
end;
function TServerMethods1.ReverseString(Value: string): string;
begin
Result := System.StrUtils.ReverseString(Value);
GetInvocationMetaData.CloseSession := True;
end;
function TServerMethods1.DownloadFile(sFile:String): TStream;
begin
{
if Assigned(FStream) then
FreeAndNil(FStream);
FStream := TFileStream.Create(sFile, fmOpenRead or fmShareDenyNone);
Result := FStream;
TFileStream(Result).Seek(0, TSeekOrigin.soBeginning);
}
result := TFileStream.Create(sFile, fmOpenRead or fmShareDenyNone);
TFileStream(Result).Seek(0, TSeekOrigin.soBeginning);
// GetInvocationMetaData.CloseSession := True;
end;
function TServerMethods1.BestaatFile(sFile: string):Boolean;
begin
Result := FileExists(sFile);
GetInvocationMetaData.CloseSession := True;
end;
end.
dfm
object ServerContainer2: TServerContainer2
OldCreateOrder = False
Height = 271
Width = 415
object DSServer1: TDSServer
Left = 96
Top = 11
end
object DSHTTPService1: TDSHTTPService
HttpPort = 7070
Server = DSServer1
Filters = <>
Left = 96
Top = 135
end
object DSServerClass1: TDSServerClass
OnGetClass = DSServerClass1GetClass
Server = DSServer1
LifeCycle = 'Invocation'
Left = 200
Top = 11
end
end
客户端代码 生成源
//
// Created by the DataSnap proxy generator.
// 2-2-2015 14:27:21
//
unit ClientClassesUnit1;
interface
uses Datasnap.DSProxyRest, Datasnap.DSClientRest, Data.DBXCommon, Data.DBXClient, Data.DBXDataSnap, Data.DBXJSON, Datasnap.DSProxy, System.Classes, System.SysUtils, Data.DB, Data.SqlExpr, Data.DBXDBReaders, Data.DBXCDSReaders, Data.DBXJSONReflect;
type
TServerMethods1Client = class(TDSAdminRestClient)
private
FEchoStringCommand: TDSRestCommand;
FReverseStringCommand: TDSRestCommand;
FDownloadFileCommand: TDSRestCommand;
FDownloadFileCommand_Cache: TDSRestCommand;
FBestaatFileCommand: TDSRestCommand;
FFreeStreamCommand: TDSRestCommand;
public
constructor Create(ARestConnection: TDSRestConnection); overload;
constructor Create(ARestConnection: TDSRestConnection; AInstanceOwner: Boolean); overload;
destructor Destroy; override;
function EchoString(Value: string; const ARequestFilter: string = ''): string;
function ReverseString(Value: string; const ARequestFilter: string = ''): string;
function DownloadFile(sFile: string; const ARequestFilter: string = ''): TStream;
function DownloadFile_Cache(sFile: string; const ARequestFilter: string = ''): IDSRestCachedStream;
function BestaatFile(sFile: string; const ARequestFilter: string = ''): Boolean;
procedure FreeStream;
end;
const
TServerMethods1_EchoString: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'Value'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 26; TypeName: 'string')
);
TServerMethods1_ReverseString: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'Value'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 26; TypeName: 'string')
);
TServerMethods1_DownloadFile: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'sFile'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 33; TypeName: 'TStream')
);
TServerMethods1_DownloadFile_Cache: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'sFile'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 26; TypeName: 'String')
);
TServerMethods1_BestaatFile: array [0..1] of TDSRestParameterMetaData =
(
(Name: 'sFile'; Direction: 1; DBXType: 26; TypeName: 'string'),
(Name: ''; Direction: 4; DBXType: 4; TypeName: 'Boolean')
);
implementation
function TServerMethods1Client.EchoString(Value: string; const ARequestFilter: string): string;
begin
if FEchoStringCommand = nil then
begin
FEchoStringCommand := FConnection.CreateCommand;
FEchoStringCommand.RequestType := 'GET';
FEchoStringCommand.Text := 'TServerMethods1.EchoString';
FEchoStringCommand.Prepare(TServerMethods1_EchoString);
end;
FEchoStringCommand.Parameters[0].Value.SetWideString(Value);
FEchoStringCommand.Execute(ARequestFilter);
Result := FEchoStringCommand.Parameters[1].Value.GetWideString;
end;
function TServerMethods1Client.ReverseString(Value: string; const ARequestFilter: string): string;
begin
if FReverseStringCommand = nil then
begin
FReverseStringCommand := FConnection.CreateCommand;
FReverseStringCommand.RequestType := 'GET';
FReverseStringCommand.Text := 'TServerMethods1.ReverseString';
FReverseStringCommand.Prepare(TServerMethods1_ReverseString);
end;
FReverseStringCommand.Parameters[0].Value.SetWideString(Value);
FReverseStringCommand.Execute(ARequestFilter);
Result := FReverseStringCommand.Parameters[1].Value.GetWideString;
end;
function TServerMethods1Client.DownloadFile(sFile: string; const ARequestFilter: string): TStream;
begin
if FDownloadFileCommand = nil then
begin
FDownloadFileCommand := FConnection.CreateCommand;
FDownloadFileCommand.RequestType := 'GET';
FDownloadFileCommand.Text := 'TServerMethods1.DownloadFile';
FDownloadFileCommand.Prepare(TServerMethods1_DownloadFile);
end;
FDownloadFileCommand.Parameters[0].Value.SetWideString(sFile);
FDownloadFileCommand.Execute(ARequestFilter);
Result := FDownloadFileCommand.Parameters[1].Value.GetStream(FInstanceOwner);
end;
function TServerMethods1Client.DownloadFile_Cache(sFile: string; const ARequestFilter: string): IDSRestCachedStream;
begin
if FDownloadFileCommand_Cache = nil then
begin
FDownloadFileCommand_Cache := FConnection.CreateCommand;
FDownloadFileCommand_Cache.RequestType := 'GET';
FDownloadFileCommand_Cache.Text := 'TServerMethods1.DownloadFile';
FDownloadFileCommand_Cache.Prepare(TServerMethods1_DownloadFile_Cache);
end;
FDownloadFileCommand_Cache.Parameters[0].Value.SetWideString(sFile);
FDownloadFileCommand_Cache.ExecuteCache(ARequestFilter);
Result := TDSRestCachedStream.Create(FDownloadFileCommand_Cache.Parameters[1].Value.GetString);
end;
function TServerMethods1Client.BestaatFile(sFile: string; const ARequestFilter: string): Boolean;
begin
if FBestaatFileCommand = nil then
begin
FBestaatFileCommand := FConnection.CreateCommand;
FBestaatFileCommand.RequestType := 'GET';
FBestaatFileCommand.Text := 'TServerMethods1.BestaatFile';
FBestaatFileCommand.Prepare(TServerMethods1_BestaatFile);
end;
FBestaatFileCommand.Parameters[0].Value.SetWideString(sFile);
FBestaatFileCommand.Execute(ARequestFilter);
Result := FBestaatFileCommand.Parameters[1].Value.GetBoolean;
end;
procedure TServerMethods1Client.FreeStream;
begin
if FFreeStreamCommand = nil then
begin
FFreeStreamCommand := FConnection.CreateCommand;
FFreeStreamCommand.RequestType := 'GET';
FFreeStreamCommand.Text := 'TServerMethods1.FreeStream';
end;
FFreeStreamCommand.Execute;
end;
constructor TServerMethods1Client.Create(ARestConnection: TDSRestConnection);
begin
inherited Create(ARestConnection);
end;
constructor TServerMethods1Client.Create(ARestConnection: TDSRestConnection; AInstanceOwner: Boolean);
begin
inherited Create(ARestConnection, AInstanceOwner);
end;
destructor TServerMethods1Client.Destroy;
begin
FEchoStringCommand.DisposeOf;
FReverseStringCommand.DisposeOf;
FDownloadFileCommand.DisposeOf;
FDownloadFileCommand_Cache.DisposeOf;
FBestaatFileCommand.DisposeOf;
FFreeStreamCommand.DisposeOf;
inherited;
end;
end.
自己的来源
unit Unit1;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls,
Vcl.Grids, Vcl.DBGrids, IPPeerClient, Datasnap.DSClientRest;
type
TForm1 = class(TForm)
Button1: TButton;
Edit1: TEdit;
Label4: TLabel;
Button5: TButton;
Edit5: TEdit;
Label5: TLabel;
Edit6: TEdit;
Label6: TLabel;
DSRestConnection1: TDSRestConnection;
procedure Button1Click(Sender: TObject);
procedure Button5Click(Sender: TObject);
private
procedure DownloadFile(sSourceFile,sTargetFile:string);
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
uses ClientClassesUnit1;
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
var oServerMethodsClient:TServerMethods1Client;
begin
oServerMethodsClient := nil;
try
try
oServerMethodsClient := TServerMethods1Client.Create(DSRestConnection1, True);
ShowMessage(oServerMethodsClient.EchoString(edit1.Text));
ShowMessage(oServerMethodsClient.ReverseString(edit1.Text));
except
on E: Exception do
begin
showmessage('Oeps echo: ' + E.Message);
end;
end;
finally
FreeAndNil(oServerMethodsClient);
end;
end;
procedure TForm1.Button5Click(Sender: TObject);
begin
DownloadFile(edit5.Text, edit6.Text);
end;
procedure TForm1.DownloadFile(sSourceFile,sTargetFile:String);
var
RetStream: TStream;
fs:TFileStream;
oServerMethodsClient:TServerMethods1Client;
begin
oServerMethodsClient := nil;
RetStream := nil;
try
try
oServerMethodsClient := TServerMethods1Client.Create(DSRestConnection1, True);
RetStream := oServerMethodsClient.DownloadFile(sSourceFile);
// oServerMethodsClient.FreeStream;
fs := TFileStream.Create(sTargetFile, fmCreate);
try
if RetStream.Size > 0 then
begin
RetStream.Position:=0;
fs.CopyFrom(RetStream, RetStream.Size);
end;
finally
fs.free;
// retstream.Free;
end;
except
on E: Exception do
begin
showmessage('Oeps download: ' + E.Message);
end;
end;
finally
FreeAndNil(oServerMethodsClient);
end;
end;
end.
dfm 来源
object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 519
ClientWidth = 959
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
PixelsPerInch = 96
TextHeight = 13
object Label4: TLabel
Left = 208
Top = 48
Width = 53
Height = 13
Caption = 'Echo string'
end
object Label5: TLabel
Left = 208
Top = 93
Width = 22
Height = 13
Caption = 'van:'
end
object Label6: TLabel
Left = 208
Top = 123
Width = 22
Height = 13
Caption = 'naar'
end
object Button1: TButton
Left = 16
Top = 43
Width = 75
Height = 25
Caption = 'echo'
TabOrder = 0
OnClick = Button1Click
end
object Edit1: TEdit
Left = 288
Top = 45
Width = 274
Height = 21
TabOrder = 1
Text = 'bla'
end
object Button5: TButton
Left = 16
Top = 88
Width = 75
Height = 25
Caption = 'haal 1 file'
TabOrder = 2
OnClick = Button5Click
end
object Edit5: TEdit
Left = 288
Top = 93
Width = 274
Height = 21
TabOrder = 3
Text = 'c:\source\temp.zip'
end
object Edit6: TEdit
Left = 288
Top = 120
Width = 274
Height = 21
TabOrder = 4
Text = 'c:\temp\temp.zip'
end
object DSRestConnection1: TDSRestConnection
Host = 'localhost'
Port = 7070
LoginPrompt = False
PreserveSessionID = False
Left = 120
Top = 16
UniqueId = '{B4909821-9EF2-42F1-AFFF-58B320C35F75}'
end
end
TStream。支持的类型列表可以在 docwiki 中找到：
Exposing DataSnap Server Methods
在你的情况下使用 TDBXStreamValue 似乎是合适的。