rssxml:RSS XML的实现方法

以下是如何生成当今比较流行RSS XML详细举例, 描述是如何从\"大智慧\"行情数据中获取数据并转化成RSS XML文件, 当然咯! 如果您想实时刷新这个RSS XML, 恐怕要去截取\"大智慧\"网络数据或内存数据了, 这里我们不谈这个.

(代码中解释比较详细, 不再多做解释)



unit STRService;

erface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, SvcMgr, Dialogs,
ExtCtrls, Contnrs, StrUtils, DB, ADODB, IniFiles, ActiveX, xmldom,
XMLIntf, msxmldom, XMLDoc;

type
TStockDayLineKDataReader = ;

TStockRSSSvc = (TService)
Timer1: TTimer;
STRConn: TADOConnection;
qryCommon: TADOQuery;
procedure ServiceExecute(Sender: TService);
procedure ServiceStart(Sender: TService; var Started: Boolean);
procedure ServiceStop(Sender: TService; var Stopped: Boolean);
procedure Timer1Timer(Sender: TObject);
private


{ Private declarations }
FLineKReader: TStockDayLineKDataReader;
public
function GetServiceController: TServiceController; override;
{ Public declarations }
function GetWorkingPath: ;
end;

TDayLineKProperty =
private
FStockID: ;
FDate: DWORD;
FOpen: DWORD;
FClose: DWORD;
FHigh: DWORD;
FLow: DWORD;
FTranQuantity: DWORD;
FSum: DWORD;
public
constructor Create (ID: ; DateVal, OpenVal, CloseVal, HighVal, LowVal,
QuantityVal, SumVal: DWORD);
destructor Destroy; override;

property ID: read FStockID;
property Date: DWORD read FDate;
property Open: DWORD read FOpen;
property Close: DWORD read

FClose;
property High: DWORD read FHigh;
property Low: DWORD read FLow;
property TranQuantity: DWORD read FTranQuantity;
property Sum: DWORD read FSum;
end;

TStockDayLineKDataReader =
private
FRSSLocation: ;
FLocation: ;
FSHDayLocation: ;
FSZDayLocation: ;
FStockList: TObjectList;
FStockIDList: TStrings;
FQuery: TADOQuery;

protected
procedure SetLocation (AValue: );
procedure Clear;
procedure GetStockIDFiles (ABuffer: TStrings; DataPath: );
procedure ReadData (AFileName: );
procedure ClearDayLineKData;
procedure WriteToDB (DayLineObj: TDayLineKProperty);
function

GetStockMarketInfo: ;

public
constructor Create (AQuery: TADOQuery; ALocation: ; RSSDest: );
destructor Destroy; override;

procedure Load;
procedure SaveToDatabase;
procedure SaveToRSS;

property Location: read FLocation write SetLocation;
end;


var
StockRSSSvc: TStockRSSSvc;

implementation

{$R *.DFM}

procedure ServiceController(CtrlCode: DWord); stdcall;
begin
StockRSSSvc.Controller(CtrlCode);
end;

function TStockRSSSvc.GetServiceController: TServiceController;
begin
Result := ServiceController;
end;

function TStockRSSSvc.GetWorkingPath: ;
begin
Result := ExtractFilePath (ParamStr (0));
end;

procedure TStockRSSSvc.ServiceExecute(Sender: TService);
begin


while not Terminated do
begin
ServiceThread.ProcessRequests(True);
end;
end;

{ TDayLineKProperty }

constructor TDayLineKProperty.Create(ID: ; DateVal, OpenVal, CloseVal, HighVal,
LowVal, QuantityVal, SumVal: DWORD);
begin
FStockID := ID;
FDate := DateVal;
FOpen := OpenVal;
FClose := CloseVal;
FHigh := HighVal;
FLow := LowVal;
FTranQuantity := QuantityVal;
FSum := SumVal;
end;

destructor TDayLineKProperty.Destroy;
begin

inherited;
end;

{ TStockDayLineKDataReader }

procedure TStockDayLineKDataReader.Clear;
begin
Assigned (FStockList) then
FreeAndNil (FStockList);
end;

procedure

TStockDayLineKDataReader.ClearDayLineKData;
begin
not Assigned (FQuery) then Exit;
with FQuery do
begin
Close;
SQL.Clear;
SQL.Add (\'DELETE * FROM db_DayLineK\');
Prepared := True;
try
try
ExecSQL;
except
_disibledevent=>do raise E.Create (E.Message);
end;
finally
Close;
end; //end try_finally
end; //end with_do
end;

const

ructor TStockDayLineKDataReader.Create (AQuery: TADOQuery; ALocation: ;
RSSDest: );
begin
FStockIDList := TStringList.Create;
FQuery := AQuery;
SetLocation (ALocation);
FRSSLocation := RSSDest;
end;

destructor TStockDayLineKDataReader.Destroy;
begin
Clear;

Assigned (FStockIDList) then
FreeAndNil (FStockIDList);

inherited;
end;

// Description: Retrieves the identiers of speicied stocks.
// Parameters:
// [out] ABuffer: species a buffer to receive the identiers of stocks.
// [in] DataPath: species the path with wildcard mask.
// Return Value: None.
// Remark: None.
procedure TStockDayLineKDataReader.GetStockIDFiles(ABuffer: TStrings; DataPath: );
var
sr: TSearchRec;
FileAttrs: Integer;
begin
(not Assigned (ABuffer)) or (Trim (DataPath) = \'\') then Exit;
ABuffer.Clear;

FileAttrs := faAnyFile;
FindFirst (DataPath, FileAttrs, sr) = 0 then
begin
repeat
ABuffer.Add (sr.Name);
until FindNext (sr) <> 0;


FindClose (sr);
end; // end
end;

function TStockDayLineKDataReader.GetStockMarketInfo: ;
var
ix: Integer;
Obj: TDayLineKProperty;
Val: ;

function GetOpen: ;
begin
Result := Format (\'开=<b>%f</b>\', [Obj.Open/1000]);
end;

function GetClose: ;
begin
Result := Format (\'收=<b>%f</b>\', [Obj.Close/1000]);
end;

function GetHigh: ;
begin
Result := Format (\'高=<b>%f</b>\', [Obj.High/1000]);
end;

function GetLow: ;
begin
Result := Format (\'低=<b>%f</b>\', [Obj.Low/1000]);
end;

function GetQuantity: ;
begin


Result := Format (\'成交量=%d\', [Obj.TranQuantity]);
end;

function GetSum: ;
begin
Result := Format (\'交易额=%d\', [Obj.Sum]);
end;

begin
for ix := 0 to Pred (FStockList.Count) do
begin
Obj := (FStockList.Items[ix] as TDayLineKProperty);
Val := Format (\'<b>%s</b>: %s %s %s %s %s %s\'#13#13,
[Obj.ID, GetClose, GetOpen, GetHigh, GetLow, GetSum, GetQuantity]);
ix mod 2 = 0 then
Val := Format (\'<font style=\"background-color:#99CCFF\">%s</font>\', [Val]);
Result := Format (\'%s%s\', [Result, Val]);
end;
end;

procedure TStockDayLineKDataReader.Load;
var
ix: Integer;
begin
Clear;
FStockList := TObjectList.Create;

GetStockIDFiles (FStockIDList,
Format (\'%s\\6*.day\', [ExcludeTrailingPathDelimiter (FSHDayLocation)]));
for ix := 0 to Pred (FStockIDList.Count) do
ReadData (Format (\'%s\\%s\', [ExcludeTrailingPathDelimiter (FSHDayLocation),
FStockIDList[ix]]));

GetStockIDFiles (FStockIDList,
Format (\'%s\\0*.day\', [ExcludeTrailingPathDelimiter (FSZDayLocation)]));
for ix := 0 to Pred (FStockIDList.Count) do


ReadData (Format (\'%s\\%s\', [ExcludeTrailingPathDelimiter (FSZDayLocation),
FStockIDList[ix]]));
end;

procedure TStockDayLineKDataReader.ReadData(AFileName: );
const
CSRecordBytes: Integer = 40;
var
DataFile: File;
Days: Integer;
DateVal,
OpenVal,
CloseVal,
HighVal,
LowVal,
SumVal,
TranQuantityVal: DWORD;
begin
AssignFile (DataFile, AFileName);
try
Re (DataFile, 1);
Days := Round (FileSize (DataFile) / CSRecordBytes);
// to locate to the latest day
Seek (DataFile, Pred (Days) * CSRecordBytes);

BlockRead (DataFile, DateVal, SizeOf (DateVal));
BlockRead (DataFile, OpenVal, SizeOf (OpenVal));
BlockRead (DataFile, HighVal, SizeOf (HighVal));
BlockRead (DataFile, LowVal, SizeOf (LowVal));
BlockRead (DataFile, CloseVal, SizeOf (CloseVal));
BlockRead (DataFile, SumVal, SizeOf (SumVal));
BlockRead (DataFile, TranQuantityVal, SizeOf (TranQuantityVal));
// skip the three reserved items left...

FStockList.Add (TDayLineKProperty.Create (
LeftStr (ExtractFileName (AFileName), 6),
DateVal, OpenVal, CloseVal, HighVal,
LowVal, TranQuantityVal, SumVal));
finally


CloseFile (DataFile);
end; // end try_finally
end;

procedure TStockDayLineKDataReader.SaveToDatabase;
var
ix: Integer;
begin
ClearDayLineKData;
for ix := 0 to Pred (FStockList.Count) do
WriteToDB (FStockList.Items[ix] as TDayLineKProperty);
end;

procedure TStockDayLineKDataReader.SaveToRSS;
var
RSSNode, ChannelNode,
ItemNode, Node: IXMLNode;
xml: TXMLDocument;
begin
Trim (FRSSLocation) = \'\' then Exit;
xml := TXMLDocument.Create (nil);
try
xml.Active := True;
xml.FileName := ExcludeTrailingPathDelimiter (FRSSLocation) + \'\\StockRSS.xml\';
xml.Version := \'1.0\';

RSSNode := xml.CreateNode (\'rss\');
xml.DocumentElement := RSSNode;
RSSNode.AttributeNodes.Add (xml.CreateNode (\'version\', ntAttribute));
RSSNode.Attributes[\'version\'] := 2;

ChannelNode := xml.CreateNode (\'channel\');
RSSNode.ChildNodes.Add (ChannelNode);

Node := xml.CreateNode (\'title\');


Node.ChildNodes.Add (xml.CreateNode (\'Stock Market\', ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'link\');
Node.ChildNodes.Add (xml.CreateNode (\'http://blog.csdn.net/wangchinaking\', ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'description\');
Node.ChildNodes.Add (xml.CreateNode (\'\', ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'language\');
Node.ChildNodes.Add (xml.CreateNode (\'en-us\', ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'pubDate\');
Node.ChildNodes.Add (xml.CreateNode (DateTimeToStr (Now), ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'lastBuildDate\');
Node.ChildNodes.Add (xml.CreateNode (DateTimeToStr (Now), ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'docs\');
Node.ChildNodes.Add (xml.CreateNode (\'http://blogs.law.harvard.edu/tech/rss\', ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'generator\');
Node.ChildNodes.Add (xml.CreateNode (\'StockRSS Generator\', ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'managingEditor\');
Node.ChildNodes.Add (xml.CreateNode (\'[email protected]\', ntText));
ChannelNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'webMaster\');
Node.ChildNodes.Add (xml.CreateNode (\'[email protected]\', ntText));
ChannelNode.ChildNodes.Add (Node);

ItemNode := xml.CreateNode (\'item\');
ChannelNode.ChildNodes.Add (ItemNode);

Node := xml.CreateNode (\'title\');
Node.ChildNodes.Add (xml.CreateNode (\'当日行情\', ntText));
ItemNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'link\');
Node.ChildNodes.Add (xml.CreateNode (\'\', ntText));
ItemNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'description\');
Node.ChildNodes.Add (xml.CreateNode (GetStockMarketInfo, ntText));
ItemNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'pubDate\');
Node.ChildNodes.Add (xml.CreateNode (DateTimeToStr (Now), ntText));
ItemNode.ChildNodes.Add (Node);

Node := xml.CreateNode (\'guid\');
Node.ChildNodes.Add (xml.CreateNode (\'\', ntText));
ItemNode.ChildNodes.Add (Node);

///////////////
xml.SaveToFile;
xml.Active := False;
finally
FreeAndNil (xml);
end;
end;

procedure TStockDayLineKDataRead

er.SetLocation(AValue: );
begin
FLocation := ExcludeTrailingPathDelimiter (AValue);
Trim (FLocation) = \'\' then
begin
FSHDayLocation := \'\';
FSZDayLocation := \'\';
Exit;
end;

FSHDayLocation := Format (\'%s\\DATA\\SHase\\Day\', [FLocation]);
FSZDayLocation := Format (\'%s\\DATA\\SZnse\\Day\', [FLocation]);
end;

procedure TStockDayLineKDataReader.WriteToDB (DayLineObj: TDayLineKProperty);
begin
(not Assigned (FQuery)) or (not Assigned (DayLineObj)) then Exit;

with FQuery do
begin
Close;
SQL.Clear;
SQL.Add (\'INSERT INTO db_DayLineK\');
SQL.Add (\'(Dlk_StockID, Dlk_Date, Dlk_Open, Dlk_High,\');
SQL.Add (\' Dlk_Close, Dlk_Low, Dlk_TranQuantity, Dlk_Sum)\');
SQL.Add (\'VALUES (:ID, :Date, :Open, :High, :Close, :Low, :Quan, :Sum)\');
with Parameters do
begin
with

ParamByName (\'ID\') do
begin
DataType := ftString;
Value := DayLineObj.ID;
end;
with ParamByName (\'Date\') do
begin
DataType := ftInteger;
Value := DayLineObj.Date;
end;
with ParamByName (\'Open\') do
begin
DataType := ftInteger;
Value := DayLineObj.Open;
end;
with ParamByName (\'High\') do
begin
DataType := ftInteger;
Value := DayLineObj.High;
end;
with ParamByName (\'Close\') do


begin
DataType := ftInteger;
Value := DayLineObj.Close;
end;
with ParamByName (\'Low\') do
begin
DataType := ftInteger;
Value := DayLineObj.Low;
end;
with ParamByName (\'Quan\') do
begin
DataType := ftLarge;
Value := DayLineObj.TranQuantity;
end;
with ParamByName (\'Sum\') do
begin
DataType := ftLarge;
Value := Round (DayLineObj.Sum/10);
end;
end; // end

with
Prepared := True;
try
try
ExecSQL;
except
// nothing to do
end; //end try_except
finally
Close;
end; //end try_finally
end; //end with_do
end;

procedure TStockRSSSvc.ServiceStart(Sender: TService;
var Started: Boolean);
var
inile: TIniFile;
begin
CoInitialize (nil);
STRConn.Close;
STRConn.ConnectionString := Format (\'Provider=%s;Data Source=%s%s;\'+


\'Persist Security Info=False;Jet OLEDB:Database Password=1428wc\',
[\'Microsoft.Jet.OLEDB.4.0\', GetWorkingPath, \'StockDB.mdb\']);
try
STRConn.Open;
except
raise Exception.Create (\'Failed to make a connection with local stock database!\');
end;

inile := TIniFile.Create (Format (\'%s%s\', [GetWorkingPath, \'.ini\']));
try
Timer1.Interval := 1000 * inile.ReadInteger (\'general\', \'AutoRefresh\', 13);
FLineKReader := TStockDayLineKDataReader.Create (
qryCommon,
inile.ReadString (\'general\', \'DZHLocation\', \'\'),
inile.ReadString (\'general\', \'RSSLocation\', \'\'));
finally
FreeAndNil (inile);
end;

Timer1.Enabled := True;
Started := True;
end;

procedure TStockRSSSvc.ServiceStop(Sender: TService; var Stopped: Boolean);
begin
Timer1.Enabled := False;
Assigned (FLineKReader) then
FreeAndNil (FLineKRead

er);
STRConn.Close;
Stopped := True;
end;

procedure TStockRSSSvc.Timer1Timer(Sender: TObject);
begin
not Assigned (FLineKReader) then Exit;
Timer1.Enabled := False;
try
FLineKReader.Load;
FLineKReader.SaveToRSS;
// FLineKReader.SaveToDatabase;
finally
Timer1.Enabled := True;
end;
end;

end.

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