Question

我有一个项目可以处理财务报告，我想让用户能够通过互联网获取此报告

我尝试使用TIdHTTPServer这是一个Indy组件，使我的应用程序可以作为HTTP服务器使用并让它能够

接收请求 - ＆gt;处理请求 - ＆gt;发回请求过程的结果

使用特殊端口。

现在我的问题是我收到了很多访问冲突错误和随机异常它看起来像线程问题或我不知道，因为如果我不使用TIdHTTPServer处理相同的请求我没有任何问题

我正在使用OnCommandGet事件处理请求并将结果发送回上下文流中的用户。

我需要的是如何在TADODataSet和TADOConnection中使用它的演示

例如我需要用户能够发送请求并且TIdHTTPServer接受请求（例如，使用ADODataSet调用存储过程并将结果作为XML文件发送回用户）

请帮助....谢谢。

Answer 1

服务器如何工作的一种可能性......

unit Unit3;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs,IDContext, IdBaseComponent, IdComponent, IdCustomTCPServer, IdTCPServer, StdCtrls, DB, ADODB;

type
  TForm3 = class(TForm)
    IdTCPServer1: TIdTCPServer;
    Memo1: TMemo;
    Button1: TButton;
    DummyConnection: TADOConnection;
    procedure Button1Click(Sender: TObject);
    procedure IdTCPServer1Execute(AContext: TIdContext);
  private
    { Private-Deklarationen }
  public
    { Public-Deklarationen }
  end;

var
  Form3: TForm3;

implementation
uses ComObj,AdoInt,ActiveX;
{$R *.dfm}
function SendStream(AContext: TIdContext; AStream: TStream): Boolean;
begin
   Result := False;
   try
     AContext.Connection.IOHandler.Write(AStream.Size);  // sending length of Stream first
     AContext.Connection.IOHandler.WriteBufferOpen;
     AContext.Connection.IOHandler.Write(AStream, AStream.Size);
     AContext.Connection.IOHandler.WriteBufferFlush;
   finally
     AContext.Connection.IOHandler.WriteBufferClose;
   end;
   Result := True;
end;

procedure TForm3.Button1Click(Sender: TObject);
begin
  IdTCPServer1.Active := true;
end;


{ Clientside function
Function RecordsetFromXMLStream(Stream:TStream): _Recordset;
var
  RS: Variant;
begin
    RS := CreateOleObject('ADODB.Recordset');
    RS.Open(TStreamAdapter.Create(Stream) as IUnknown);
    Result := IUnknown(RS) as _Recordset;
end;
}

Procedure RecordsetToXMLStream(const Recordset: _Recordset;Stream:TStream);
var
  RS: Variant;
begin
    if Recordset = nil then Exit;
    RS := CreateOleObject('ADODB.Recordset');
    RS := Recordset;
    RS.Save(TStreamAdapter.Create(stream) as IUnknown, adPersistXML);
    Stream.Position := 0;
end;

Procedure GetQueryStream(Const s,ConStr:String;ms:TMemoryStream);
var
 AC:TAdoConnection;
 ads:TAdodataset;
begin
 AC:=TAdoConnection.Create(nil);
 try
 ads:=TAdodataset.Create(nil);
   try
     ads.Connection := AC;
     AC.ConnectionString := ConStr;
     ads.CommandText := s;
     ads.Open;
     RecordsetToXMLStream(ads.Recordset,ms);
   finally
     ads.Free
   end;
 finally
   AC.Free
 end;

end;

procedure TForm3.IdTCPServer1Execute(AContext: TIdContext);
var
 cmd:String;
 ms:TMemoryStream;
begin
     CoInitialize(nil);
     AContext.Connection.IOHandler.Readln(cmd);
     ms:=TMemoryStream.Create;
     try
     GetQueryStream('Select * from Adressen',DummyConnection.ConnectionString,ms);
     ms.Position := 0;
     SendStream(AContext,ms);
     AContext.Connection.Socket.CloseGracefully;
     finally
        ms.Free;
        CoUninitialize;
     end;

end;
end.

构建HTTP Server应用程序

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