urdffeed.pas

自己写的一个 RSS 阅读器

unit uRDFFeed;

interface

uses Classes, uW3CDTF, FastStringFuncs, uRssBase, MSXML2_TLB, uConstants;

type

TRDFFeed = class(TInterfacedObject, IRSSBase)
private
  FDoc:IXMLDOMDocument2;
	fItems : IRSSItemBaseList;
  FTitle, FDescription : string;
  FVersion, FLink, FCreator : WideString;
protected
  function Get_Version : WideString;
  function Get_Title : string;
  function Get_Link: WideString;
  function Get_Description: string;
  function Get_Creator: WideString;
  function Get_Items: IRSSItemBaseList;
public
	constructor Create(theDoc : IXMLDOMDocument2);
  property Items:IRSSItemBaseList read fItems;
  property Version: WideString read Get_Version;
  property Title: string read Get_Title;
  property Link: Widestring read Get_Link;
  property Description: string read Get_Description;
  property Creator: WideString read Get_Creator;
end;

TRDFItems = class(TInterfacedObject, IRSSItemBaseList)
private
  fItems : TList;
  fNode:IXMLDOMNode;
protected
  procedure Add(item : TInterfacedObject);
  function Get_Item(index : integer): IRSSItemBase;
  function Get_Count(): integer;
public
	constructor Create(theNode:IXMLDOMNode);
end;

TRDFItem = class(TInterfacedObject, IRSSItemBase)
  private
    FAuthor: string;
    FTitle: string;
    FPubDate: TW3CDTF;
    FGuid: WideString;
    FLink: WideString;
    FDescription: string;
    FCategory : string;

    fNode:IXMLDOMNode;
  protected
    function Get_Author: string;
    function Get_Title: string;
    function Get_PubDate: TW3CDTF;
    function Get_Guid: WideString;
    function Get_Link: WideString;
    function Get_Category: string;
    function Get_Creator: WideString;
    function Get_Description: string;
  public
		constructor Create(theNode : IXmlDOMNode);
  end;

  function GetRDFFeed(Doc: IXMLDOMDocument2): IRSSBase;

implementation

uses SysUtils;

function GetRDFFeed(Doc: IXMLDOMDocument2): IRSSBase;
begin
  Result := TRDFFeed.Create(Doc) as IRSSBase;
end;

{ TRDFFeed }

constructor TRDFFeed.Create(theDoc : IXMLDOMDocument2);
var
	i : integer;
  channelNodes : IXMLDOMNodeList;
  Node: IXmlDomNode;
begin
  FDoc:=theDoc;
	node := FDoc.documentElement;
  fItems := TRDFItems.Create(node);

  FCreator := GetNodeVal(node, 'channel/creator');
 	FDescription := GetNodeVal(node, 'channel/description');
  FTitle := ExtractNonHTML(GetNodeVal(node, 'channel/title'));
  FLink := GetNodeVal(node, 'channel/link');
	FVersion := 'RDF 1.0';

  channelNodes := node.SelectNodes('item');
  for i := 0 to channelNodes.length - 1 do
  	fitems.Add( TRDFItem.Create(channelNodes.item[i]) );
end;

function TRDFFeed.Get_Creator: WideString; begin Result := FCreator; end;
function TRDFFeed.Get_Description: string; begin Result := FDescription; end;
function TRDFFeed.Get_Items: IRSSItemBaseList; begin Result := fItems; end;
function TRDFFeed.Get_Link: WideString; begin Result := FLink; end;
function TRDFFeed.Get_Title: string; begin Result := FTitle; end;
function TRDFFeed.Get_Version: WideString; begin Result := FVersion; end;

{ TRDFItems }

constructor TRDFItems.Create(theNode:IXMLDOMNode);
begin
   fItems := TList.Create();
   fNode:=theNode;
end;
procedure TRDFItems.Add(item: TInterfacedObject); begin fItems.Add(item); end;
function TRDFItems.Get_Count: integer; begin Result := fItems.Count; end;
function TRDFItems.Get_Item(Index: Integer): IRSSItemBase; begin Result := TRDFItem(fItems[index]); end;

{ TRDFItem }
constructor TRDFItem.Create(theNode: IXmlDOMNode);
var
	str : WideString;
  tmpNode : IXmlDOMNode;
begin
  FAuthor:='';
  FTitle:='';
  FGuid:='';
  FLink:='';
  FDescription:='';
  FCategory := '';
  if assigned(theNode) then begin
    fNode:=theNode;

    FAuthor := getNodeVal(thenode, 'author');
    if FAuthor = '' then FAuthor := getNodeVal(thenode, 'dc:creator');
    FCategory := getNodeVal(thenode, 'category');

    FTitle := ExtractNonHTML(getNodeVal(thenode, 'title'));
    FGuid := getNodeVal(thenode, 'guid');
    FLink := getNodeVal(thenode, 'link');
    try
      str := getNodeVal(thenode, 'dc:date');
      if str <> '' then begin
          FPubDate := TW3CDTF.Create(str);
      end else
          FPubDate := TW3CDTF.Create(getNodeVal(thenode, 'date'));
    except
      FPubDate := TW3CDTF.CreateDateTime(0);
    end;
    try
      tmpNode := thenode.selectSingleNode('body');
      if Assigned(tmpnode) then
        FDescription := tmpNode.xml
      else
        FDescription := getNodeVal(thenode, 'description');
    except
      FDescription := getNodeVal(thenode, 'description');
    end;
  end else
  	FPubDate := TW3CDTF.CreateDatetime(0);
end;

function TRDFItem.Get_Author: string; begin Result := FAuthor; end;
function TRDFItem.Get_Category: string; begin Result := FCategory; end;
function TRDFItem.Get_Creator: WideString; begin Result := Get_Author(); end;
function TRDFItem.Get_Description: string; begin Result := FDescription; end;
function TRDFItem.Get_Guid: WideString; begin Result := FGuid; end;
function TRDFItem.Get_Link: WideString; begin Result := FLink; end;
function TRDFItem.Get_PubDate: TW3CDTF; begin Result := FPubDate; end;
function TRDFItem.Get_Title: string; begin Result := FTitle; end;

end.