Title: HTML DOM parser + NODE viewer
Question: Resolve DOM tree using Parse function.
Also build basic tree with preview option.
Answer:
Download complete article:
http://web.vip.hr/inga.vip/domnodes.zip
if you don't have mshtml_tlb already installed,just import ActiveX named
"Microsoft HTML Object Library"
unit DOMparser;
interface
uses windows,MSHTML_tlb, ActiveX, ComObj;
const
IID_IPersistStreamInit : TGUID = '{7FD52380-4E07-101B-AE2D-08002B2EC713}';
type TDomStringParser=class
private
pDoc : IHTMLDocument2;
pNewDoc : IHTMLDocument2;
pPersist : IPersistStreamInit;
pMS : IMarkupServices;
pMC : IMarkupContainer;
pMkStart : IMarkupPointer;
pMkFinish : IMarkupPointer;
pBody : IHTMLElement;
didInit : boolean;
IsInitialized:longbool;
protected
function LoadString (var OutData:string;cFileName:string):longbool;
function CreateAll:longbool;
function FreeAll:longbool;
public
property Document:IHTMLDocument2 read pNewDoc;
constructor Create;
destructor Destroy;override;
function ParseDocument (const FileName:string):longbool;
function ParseString (const HtmlString:string):longbool;
end;
implementation
{ TDomStringParser }
function TDomStringParser.LoadString (var OutData:string;cFileName:string):longbool;
var
fLen:cardinal;
fH:cardinal;
xS:cardinal;
xH:cardinal;
begin
result:=false;
fH:=CreateFile(pointer(cFileName), GENERIC_READ ,0,0,OPEN_EXISTING,0,0);
if fH=INVALID_HANDLE_VALUE then exit;
xS:=GetFileSize(fh,addr(xH));
setlength(OutData,xS);
if ReadFile(fH,pointer(OutData)^,length(OutData),fLen,0) then result:=true;
CloseHandle(fH);
end;
function TDomStringParser.ParseDocument (const FileName:string):longbool;
var
cString:string;
cW:widestring;
begin
result:=false;
if not IsInitialized then exit;
if not LoadString(cString,FileName) then exit;
cW:=widestring(cString);
setlength(cString,0);
//Po?ni...
pMS.ParseString(word(cW[1]), 0, pMC, pMkStart, pMkFinish);
if (pMC nil) then
begin
pMC.QueryInterface(IID_IHTMLDocument, pNewDoc);
if (pNewDoc nil) then
result:=true;
end;
end;
function TDomStringParser.ParseString(
const HtmlString: string): longbool;
var
cW:widestring;
begin
result:=false;
if not IsInitialized then exit;
cW:=widestring(HtmlString);
//Po?ni...
pMS.ParseString(word(cW[1]), 0, pMC, pMkStart, pMkFinish);
if (pMC nil) then
begin
pMC.QueryInterface(IID_IHTMLDocument, pNewDoc);
if (pNewDoc nil) then
result:=true;
end;
end;
function TDomStringParser.CreateAll: longbool;
begin
result:=false;
CoCreateInstance(CLASS_HTMLDocument, nil, CLSCTX_INPROC_SERVER, IID_IHTMLDocument2, pDoc);
if pDoc = nil then exit;
pDoc.QueryInterface(IID_IPersistStreamInit, pPersist);
if pPersist = nil then exit;
pPersist.InitNew;
pPersist._Release;
pDoc.QueryInterface(IID_IMarkupServices, pMS);
if pMS = nil then exit;
pMS.CreateMarkupPointer(pMkStart);
pMS.CreateMarkupPointer(pMkFinish);
result:=true;
end;
function TDomStringParser.FreeAll: longbool;
begin
IsInitialized:=false;
end;
constructor TDomStringParser.Create;
begin
inherited;
IsInitialized:=CreateAll;
end;
destructor TDomStringParser.Destroy;
begin
FreeAll;
end;
end.