Converter RTF para HTML

unit rtf2html; (* -------------------------------------------------------------------------------- Revision history: Nb. Date: Author What was done. 004 01-Oct-1999 CMS MAJOR work done-- --Inserted end tags where necessary --Fixed bug that would not modify the color of a font when the rest of the font was unchanged --cleaned up the code and commented 003 ? ? ? 002 21-aug-1997 TSE Minor (very minor) cleanup before release 001 20-aug-1997 TSE Unit created - RtfToHTML function designed and written. Author list: TSETroels Skovmand EriksenTSEriksen@cyberdude.com TSErikse@post8.tele.dk ? ? ? CMS Christopher Matthew Sansone ChrisSansone@rocketmail.com Supported features: rev. 001Indents, Bullets, Left-, Centered & Rightjustified text, Text styles (bold, italics and underline), Fonts (face, size, color). rev. 002- do - rev. 3? -------------------------------------------------------------------------------- This unit and all procedures and functions herein is released as freeware. Any components or units created using this unit or portions hereoff must be released as freeware (This does not cover applications - they may be shareware/commercial as needed). Part of the function RtfToHTML may be covered by some obscure Microsoft copyright since it reads the RTF format - check it out yourself, if you do something worthwhile. Please let this preface stay if you publish a changed/updated version of this unit and write all changes the ´Revision history´ section above. Who-Dun-it information should be inserted in the ´Author list´ and the ´Supported features´ section should be updated. This makes it easier to pass the blame :-) I´m finished with this unit for now - but please email a copy of any changes you make to me - Troels S Eriksen. -------------------------------------------------------------------------------- The following should be fixed - if anybody want to do it? * Should be rewritten into a conversion class - could be tricky, since it seems like a stream only contains 4 Kb at a time ... * Code should be cleaned up - this below is not that fast ... * The indents (\li#) should be translated to <BLOCKQUOTE> or just a <UL> with no <LI> elements. * The hanging paragraphs should be translated to definitionlists ( the <DL COMPACT> <DT> term <DD> definition </DL> structure ) * Tabs (\tab) should be fixed somehow ( heck, I DO want a <TAB> code ! ) * Embedded objects / pictures should be converted to .gif´S - I know it´S possible * Some nice way to handle links ( the way .RTF-sources for helpfiles do ? ) * A even more nice way of handling tables - could fix the indent / tab-problems as well -------------------------------------------------------------------------------- The idea and logic behind this weirdo function : Well, the idea was to write a pascal RTF-2-HTML converter which doesn´t just do some ´search and replace´ - but actually converts the dammed stuff. Since there´S a difference between HTML and RTF in the code-sequencing, I decided to try storing all paragraph and textformatting information in two records (RTFParagraphFormat and RTFTextFormat) and only write the contents of these to the output ´stream´ when needed. This first attempt is successfull - not highly, but it´ll convert the contents of a TRichEdit control and most other .RTF documents to HTML and keep the general layout. Enjoy it Troels S Eriksen, Denmark -------------------------------------------------------------------------------- *) {$LONGSTRINGS ON} interface uses ComCtrls; //To use RtfToHtml, just pass the RTF-encoded string, and it will return //the HTML-encoded string. To use RichEditHTML, simply pass the TRichEdit, //and it will return the HTML. function RtfToHtml(const RTF: String): String; function RichEditHTML(ARichEdit: TRichEdit): String; implementation uses Classes, SysUtils, Forms; function RtfToHtml(const RTF: String): String; type THTMLTagState = (htsNotActivated, htsMustActivate, htsActivated, htsMustDeactivate); THTMLTagType = (hftNone, hftBold, hftUnderline, hftItalics, hftFont, hftParagraph); THTMLTagTypes = set of THTMLTagType; THTMLBulletType = (hbtNone, hbtListOpen, hbtListItemOpen, hbtListItemClose, hbtListClose, hbtBreak); TRTFFontState = record FontTable: Boolean; ColorTable: Boolean; FontList, ColorList: TStringList; end; TRTFParagraphFormat = record Alignment: TAlignment; Bullets: THTMLBulletType; Written: Boolean; end; TRTFTextFormat = record WriteFont: Boolean; DefaultFont: Integer; Font: Integer; FontSize: Integer; Color: Integer; Bold: THTMLTagState; Italics: THTMLTagState; Underline: THTMLTagState; Written: Boolean; end; var Index : Integer; // index of the current character RTFParagraphFormat : TRTFParagraphFormat; //paragraph formatting record RTFTextFormat : TRTFTextFormat; //text formatting record RTFFontState : TRTFFontState; //font state record HTMLTagOrder: array[0..4] of THTMLTagType; //ordered array of tags Keyword, FullKeyword: String; //current and full RTF tag ActiveTags: THTMLTagTypes; //active formatting tags Group: Integer; //current number of groups the code is nested in FColor: String[10]; //RTF color information FFont: String[63]; //RTF font information procedure AddTagType(AHTMLTagType: THTMLTagType); {adds the current tag type to the tag array} var i: Integer; begin For i := 0 to High(HTMLTagOrder) do //loop through the array If HTMLTagOrder[i] = AHTMLTagType then //the tag type is already in Exit; //since the tag type is already there, do not add again //the most recent tags are in the front of the array For i := High(HTMLTagOrder) downto 0 do //loop from last to first If HTMLTagOrder[i] = hftNone then begin //empty space in array HTMLTagOrder[i] := AHTMLTagType; //set the empty entry to the tag type Exit; //finished, so exit end; end; procedure InsertTag(AHTMLTagType: THTMLTagType; var S: String); {Inserts the necessary tag into S -- If UpdateArray is True, the array will be updated to include this entry} begin Case AHTMLTagType of hftBold: //add a bold tag begin S := S + ´<B>´; RTFTextFormat.Bold := htsActivated; //update the text format record end; hftItalics: //add an italics tag begin S := S + ´<I>´; RTFTextFormat.Italics := htsActivated; //update text format record end; hftUnderline: //add an underline tag begin S := S + ´<U>´; RTFTextFormat.Underline := htsActivated; //update text format record end; hftFont: //add a font tag begin With RTFTextFormat do //create font tag with current font info S := S + ´<FONT FACE=´´ + RTFFontState.FontList[Font] + ´´ COLOR=´´ + RTFFontState.ColorList[Color] + ´´ SIZE=´´ + IntToStr(FontSize) + ´´>´; end; hftParagraph: //add a paragraph tag begin case RTFParagraphFormat.Alignment of //create aligned paragraph tag taLeftJustify : S := S + #1310´<P>´; taRightJustify: S := S + 1310´<P ALIGN=RIGHT>´; taCenter : S := S + 1310´<P ALIGN=CENTER>´; end; end; end; AddTagType(AHTMLTagType); //update the array end; procedure WriteEndTag(AHTMLTagType: THTMLTagType; var S: String); {Writes the end tag of the tag type into S and updates the record-- ***Methods should call WriteEndTags instead, because this method does not update the array of tags.} begin Case AHTMLTagType of hftBold: //write bold end tag begin S := S + ´</B>´; RTFTextFormat.Bold := htsNotActivated; //update format record end; hftItalics: //write italics end tag begin S := S + ´</I>´; RTFTextFormat.Italics := htsNotActivated; //update format record end; hftUnderline: //write underline end tag begin S := S + ´</U>´; RTFTextFormat.Underline := htsNotActivated; //update format record end; hftFont: //write font end tag begin S := S + ´</FONT>´; end; hftParagraph: //write paragraph end tag begin S := S + ´</P>´#13101310; end; end; end; procedure WriteEndTags(var S: String; AExcludeTags: THTMLTagTypes); {Writes the end tags for all items in the array except for those excluded} var i: Integer; begin For i := 0 to High(HTMLTagOrder) do //loop through the array If not (HTMLTagOrder[i] in AExcludeTags) then begin //not excluded WriteEndTag(HTMLTagOrder[i], S); //write the end tag into S HTMLTagOrder[i] := hftNone; //reset the entry in the array end; end; procedure WriteChar(C: Char); {Processes the character to HTML and writes the character to the result-- This method also checks to see if text and paragraph tags must be inserted} var S : string; //temporary string begin Application.ProcessMessages; //allow the application to process S := ´´; //initialize the return string If (not RTFParagraphFormat.Written) or (not RTFTextFormat.Written) then //either the paragraph format or text format will be changed-- //must keep track of the current format tags in order to deactivate, //add other tags, and reactivate With RTFTextFormat do begin ActiveTags := []; //initialize If Bold = htsActivated then //Bold is staying activated ActiveTags := ActiveTags + [hftBold]; //add Bold to set If Italics = htsActivated then //Italics is staying activated ActiveTags := ActiveTags + [hftItalics]; //add Italics to set If Underline = htsActivated then //Underline is staying activated ActiveTags := ActiveTags + [hftUnderline]; //add Underline to set end; With RTFParagraphFormat do //write the necessary paragraph tags If not Written then begin //changes must be made WriteEndTags(S, []); //close all open tags //write the proper paragraph tags case Bullets of hbtNone: //a new paragraph must be created begin InsertTag(hftParagraph, S); //insert new paragraph tag RTFTextFormat.WriteFont := True; //will add the new font tag RTFTextFormat.Written := False; //must write text format tags end; hbtListOpen: //start a list begin S := S + #1310´<UL>´; //write the tag RTFTextFormat.WriteFont := True; //will add the new font tag RTFTextFormat.Written := False; //must write text format tags end; hbtListItemOpen: //add a new list item begin S := S + 13109´<LI>´; //write the tag RTFTextFormat.WriteFont := True; //will add the new font tag RTFTextFormat.Written := False; //must write text format tags end; hbtListItemClose: //close a list item begin S := S + ´</LI>´; //write the close list item tag end; hbtListClose: //close a list begin S := S + #1310´</UL>´1310; //write the close list tag Bullets := hbtNone; //set paragraph formatting to standard (<P>) end; hbtBreak: //break -- not currently used begin S := S + ´<BR>´13101603216032160; //insert a break Bullets := hbtNone; //set paragraph formatting to standard (<P>) end; end; Written := True; //flag -- the paragraph tags have been written end; { RTFParagraphFormat } With RTFTextFormat do //now write any necessary text format tags If (not Written) and //changes must be made (RTFParagraphFormat.Bullets <> hbtListOpen) then begin WriteEndTags(S, [hftFont, hftParagraph]); //write format end tags If WriteFont then begin //the font has changed--must write font WriteEndTags(S, [hftParagraph]); //close the font tag if necessary InsertTag(hftFont, S); //insert the new font tag WriteFont := False; //flag -- font has been written end; If (hftBold in ActiveTags) or (Bold = htsMustActivate) then //Bold is either currently active or must be activated InsertTag(hftBold, S); //insert the Bold tag If (hftItalics in ActiveTags) or (Italics = htsMustActivate) then //Italics is either currently active or must be activated InsertTag(hftItalics, S); //insert the Italics tag If (hftUnderline in ActiveTags) or (Underline = htsMustActivate) then //Underline is either currently active or must be activated InsertTag(hftUnderline, S); //insert the Underline tag Written := True; //flag -- text formatting tags have been handled end; //Now write the characters and tags case C of #0 : Result := Result + S; // Writes pending codes only 9 : Result := Result + S + 9; // Writes tab char ´>´ : Result := Result + S + ´>´; // Writes ´greater than´ ´<´ : Result := Result + S + ´<´; // Writes ´less than´ else Result := Result + S + C; // Writes the passed character end; end; { WriteChar } function Resolve(C: Char): Integer; {Converts the character to its integer value -- used to decode \´ to an ansi-Value } begin case Byte(C) of 48..57 : Result := Byte(C) - 48; 65..70 : Result := Byte(C) - 55; else Result := 0; end; end; { resolve } function GetFullKeyword(ARTF: String; StartPos: Integer): String; {Returns the entire keyword for a particular key--keys are separated by ´ ´} begin Delete(ARTF, 1, StartPos - 1); //remove all text before the key Result := Copy(ARTF, 1, Pos(´ ´, ARTF) - 1); //return all text before ´ ´ end; function TagInKeyword(ARTFTag: String): Boolean; {Returns true if a particular tag is in the current keyword (e.g. ´\b´)} begin Result := Pos(ARTFTag, FullKeyword) > 0; //return true if substring found end; function CollectCode(I: Integer): Integer; {Parses and handles the RTF code beginning at position I to convert to HTML} var Value: String; A: Integer; begin Keyword := ´´; //initialize the keyword // First - check if Keyword is any ´special´ Keyword or is a normal one ... case RTF[i + 1] of //look at the current character ´*´ : begin // Ignore all code until the end of the Group a := Group; //get the current embedded Group count repeat //loop through each character case RTF[i] of ´{´ : Inc(Group); //another Group is opened -- increment count ´}´ : Dec(Group); //a Group is closed -- decrement embedded count end; Inc(i); //go to the next character until (Group + 1) = a; //until the start of another Group is found Result := i - 1; //return the position of the Group start end; #39 : begin // Decode hex Value WriteChar(Char(Resolve(UpCase(RTF[i + 2])) * 16 + Resolve(UpCase(RTF[i + 3])))); Inc(i, 3); //go three spaces ahead Result := i; //return the next position end; ´\´,´{´,´}´ : begin // Return special character WriteChar(RTF[i + 1]); //write the character Inc(i); //go to the next character Result := i; //return the next character end; else begin //must be a keyword repeat //get the keyword Keyword := Keyword + RTF[i]; //add the next character to the keyword Inc(i); //go to the next character until (RTF[i] in [´{´,´\´,´}´,´ ´,´;´,´-´,´0´..´9´]); //end of keyword // Second - get any Value following ... Value := ´´; //initialize the value While (RTF[i] in [´a´..´z´,´-´,´0´..´9´]) do begin //value exists Value := Value + RTF[i]; //add the character to value Inc(i); //go to the next character end; while (RTF[i] in [´{´, ´}´, ´;´, ´ ´]) do //character can be ignored Inc(i); //ignore the current character Result := i - 1; //return position of previous character // Check which Keyword it is and perform the necessary functionality-- // Tested--Using IF THEN ELSE is 10¬ more efficient than calling EXIT if Keyword = ´\par´ then //New paragraph or bullet item with RTFParagraphFormat do begin Written := False; //update the HTML tags if Bullets = hbtListItemOpen then begin //list item currently open Bullets := hbtListItemClose; //must close the list item WriteChar(#0); //write the change end end else if Keyword=´\f´ then //font change case RTFFontState.FontTable of True: //must add the current font to the font list begin FFont:=´´; //initialize current font While RTF[i]<>´ ´ do // Ignore font family info, etc. Inc(i); Inc(i); //go to next character While RTF[i]<>´;´ do begin //Read font name until ´;´ FFont := FFont + RTF[i]; //add character to font name Inc(i); //go to the next character end; Dec(Group); //finished a Group, so close it Result := i + 1; //Move one beyond Group end RTFFontState.FontList.Add(FFont); //Add font name to font list end; False: With RTFTextFormat do begin //Use name already in font list a := StrToIntDef(Value, 0); //get index of font in font list if Font <> a then begin //Font has changed--must make HTML tag WriteFont := True; //must write the new font Written := False; //have not written new text formatting yet Font := a; //set the index of the current font end; end; end else if Keyword = ´\plain´ then //original text format with RTFTextFormat do begin //must reset all text attributes FullKeyword := GetFullKeyword(RTF, i); //get full keyword If (Color <> 0) and (not TagInKeyword(´\cf´)) then begin //the current color is not the default color, and the color will //not be updated in this keyword--must reset color and write font Color := 0; //reset the color WriteFont := True; //must write the new font Written := False; //have not written the new text formatting yet WriteChar(#0); //write the new tags end else begin //the color does not need to be updated If (bold = htsActivated) {and (not TagInKeyword(´\b´))} then //Bold is no longer active, so it must be deactivated Bold := htsMustDeactivate; //deactivate Bold If (Italics = htsActivated) {and (not TagInKeyword(´\i´))} then //Italics is no longer active, so it must be deactivated Italics := htsMustDeactivate; //deactivate Italics If (Underline = htsActivated) {and (not TagInKeyword(´\ul´))} then //Underline is no longer active, so it must be deactivated Underline := htsMustDeactivate; //deactivate Underline if (Bold = htsMustDeactivate) or (Italics = htsMustDeactivate) or (Underline = htsMustDeactivate) then begin //one or more attributes have changed--must write the new tags Written := False; //have not written new text formatting yet WriteChar(#0); //write the new tags end else //no attributes have changed -- no need to write anything WriteFont := False; //do not update the font end; end else if Keyword = ´\fs´ then //modify the font size with RTFTextFormat do begin case StrToIntDef(Value, 11) div 2 of 1.. 5 : a := 1; //set an appropriate font size 6.. 9 : a := 2; 10..11 : a := 3; 12..13 : a := 4; 14..15 : a := 5; else a := 6; end; if a <> FontSize then begin //the font size has changed FontSize := a; //set the new font size Written := False; //have not written the new font size yet WriteFont := True; //write the new font end; end else if Keyword = ´\tab´ then //tab character WriteChar(#9) //send a tab character--displayed as a space in HTML else if Keyword = ´\ul´ then begin //Underline is activated with RTFTextFormat do if Underline = htsNotActivated then begin //must activate Underline Underline := htsMustActivate; //activate Underline Written := False; //have not written new attribute yet end; end else if Keyword = ´\b´ then begin //Bold is activated with RTFTextFormat do if Bold = htsNotActivated then begin //must activate Bold Bold := htsMustActivate; //activate Bold Written := False; //have not written new attribute yet end; end else if Keyword = ´\i´ then begin //Italics is activated with RTFTextFormat do if Italics = htsNotActivated then begin //must activate Italics Italics := htsMustActivate; //activate Italics Written := False; //have not written new attribute yet end; end else if Keyword = ´\cf´ then //font color has been changed with RTFTextFormat do begin a := StrToIntDef(Value, 0); //get index of color in the color list If Color <> a then begin //the color has changed Color := a; //set the new color Written := False; //have not written the new color yet WriteFont := True; //write the new font end; end else if Keyword = ´\qc´ then begin //paragraph must be centered With RTFParagraphFormat do If Bullets = hbtNone then begin Alignment := taCenter; //align the paragraph to center Written := False; //alignment has not been written yet end; end else if Keyword = ´\qr´ then begin //paragraph must be right-aligned With RTFParagraphFormat do If Bullets = hbtNone then begin Alignment := taRightJustify; //align the paragraph to right Written := False; //alignment has not been written yet end; end else if Keyword = ´\pntext´ then //Start bullet list item with RTFParagraphFormat do begin Written := False; //have not written the bullet tag yet Bullets := hbtListItemOpen; //the current item is a new list item a := Group; //get current embedded group count repeat //go through the RTF until a group is closed case RTF[i] of ´{´: Inc(Group); //new group to open--increment Group ´}´: Dec(Group); //group is closed--decrement Group end; Inc(i); //go to the next character until (Group + 1) = a; //until the end of a group has been reached Result := i - 1; //go to the end of the group end else if Keyword = ´\fi´ then //a bullet list must be started with RTFParagraphFormat do begin Written := False; //bullet tag has not been written Bullets := hbtListOpen; //the current bullet type is an open list WriteChar(#0); //write the open list tag end else if Keyword = ´\pard´ then //end of paragraph / bullet list with RTFParagraphFormat do begin Alignment := taLeftJustify; //reset the paragraph alignment to left Written := False; //have not written the paragraph change yet If Bullets <> hbtNone then begin //currently in an open bullet list Bullets := hbtListClose; //close the bullet list WriteChar(0); //write the close list tag end; end else if Keyword = ´\red´ then //setting red color FColor := ´´ + IntToHex(StrToIntDef(Value, 255), 2) //Get red color else if Keyword = ´\green´ then //setting green color FColor := FColor + IntToHex(StrToIntDef(Value, 255), 2) //Get color else if Keyword = ´\blue´ then begin //setting blue color--finished FColor := FColor + IntToHex(StrToIntDef(Value, 255), 2); //Get color RTFFontState.ColorList.Add(FColor); //Add RGB to the color list end else if Keyword = ´\deff´ then //default font index with RTFTextFormat do DefaultFont := StrToIntDef(Value, 0) //set the default font index else if Keyword = ´\fonttbl´ then //must create an entry in font list RTFFontState.FontTable := True //initialize creation of font list else if Keyword = ´\colortbl´ then //must create a color list RTFFontState.ColorTable := True //must create an entry in color list else if Keyword = ´\deflang´ then begin //Update is finished RTFFontState.FontTable := False; //finished creating font list entry With RTFParagraphFormat do begin // reset paragraph format Alignment := taLeftJustify; //reset paragraph alignment to left Written := False; //have not written new paragraph tags yet Bullets := hbtNone; //reset bullets to standard paragraphs end; With RTFTextFormat do begin //reset font format Font := DefaultFont; //set the font index to the default index FontSize := 3; //reset the font size to default Color := 0; //reset the color index to the default index Bold := htsNotActivated; //initialize bold Italics := htsNotActivated; //initialize italics Underline := htsNotActivated; //initialize underline Written := False; //have not written the new font settings yet end; RTFFontState.ColorTable := True; //must start creating color entry end; end; end; end; function CleanUp(S: String): String; {Occurs when the HTML code has been completed-- Closes any remaining open tags and returns the updated code} begin WriteEndTags(S, []); Result := S; end; var i: Integer; begin try For i := 0 to High(HTMLTagOrder) do //loop through entire array HTMLTagOrder[i] := hftNone; //initialize the entire array to hftNone RTFFontState.FontList := TStringList.Create; //Create font list RTFFontState.ColorList := TStringList.Create; //Create color list RTFParagraphFormat.Written := True; //initialize RTFTextFormat.Written := True; //initialize--will be false on first format Index := 0; //initialize the index Result := ´´; //initialize the result repeat Inc(Index); //go to the next character case RTF[Index] of #0..31 : ; //ASCII control characters -- ignore ´{´: Inc(Group); //new group -- increment embedded group count ´}´: Dec(Group); //closed group -- decrement embedded group count ´\´: Index := CollectCode(Index); //RTF keyword--update HTML tags else begin //a standard character -- just write it to the result WriteChar(RTF[Index]); //Write char and any pending HTML codes Inc(Index); //Speed-write normal characters until next special one while (Index < Length(RTF)) and not (RTF[Index] in [´{´,´}´,´\´,´<´,´>´,00..31]) do begin //have not reached end of RTF yet and current character is standard Result := Result + RTF[Index]; //add current character to result Inc(Index); //go to next result end; Dec(Index); //go back one character (incremented one too many times) end; end; until Index = Length(RTF); //until all code has been processed finally Result := CleanUp(Result); //Return the completed HTML document With RTFFontState do begin FontList.Free; //destroy the font list ColorList.Free; //destroy the color list end; end; end; function RichEditHTML(ARichEdit: TRichEdit): String; var MS: TMemoryStream; RichText: String; begin RichText := ´´; MS:= TMemoryStream.Create; //create a memory stream try ARichEdit.Lines.SaveToStream(MS); //save the RTF text to stream RichText := PChar(MS.Memory); //get the resulting text stream Result := RtfToHtml(RichText); finally MS.Free; //destroy the memory stream end; end; end.