How to use DefineProperties in a custom Class Object for dynamic Arrays - Delphi -

-

i'm trying create own class object , use store various data types application, works fine when using published properties, can stream these disk , no problems. need stream dynamic arrays of integer types well.

            type               tarrayofinteger = array of integer;                tsetting = class(tcomponent)               private                 fintval: integer;                 fintarr: tarrayofinteger;                 procedure readintarr(reader: treader);                 procedure writeintarr(writer: twriter);               protected                 procedure defineproperties(filer: tfiler); override;               published                 property intval: integer read fintval write fintval;                 property intarr: tarrayofinteger read fintarr write fintarr;               end;              { tsetting }              procedure tsetting.defineproperties(filer: tfiler);             begin               inherited;               filer.defineproperty('intarr', readintarr, writeintarr, true);             end;             procedure tsetting.readintarr(reader: treader);             var               i: integer;               lvval:integer;             begin               i:=low(fintarr);               reader.readlistbegin;               {j := reader.readinteger();               setlength(fintarr, j);               := 0 j - 1               begin                 fintarr[i] := reader.readinteger();               end;}             while not reader.endoflist begin                 fintarr[i]:=reader.readinteger;                 inc(i);               end;               reader.readlistend;             end;              procedure tsetting.writeintarr(writer: twriter);             var               i: integer;             begin               writer.writelistbegin;               //writer.writeinteger(integer(length(fintarr)));               := low(fintarr) high(fintarr)               begin                 writer.writeinteger(fintarr[i]);               end;               writer.writelistend;             end;              function classtostr(pvclass:tcomponent):ansistring;             var               instream, outstream: tmemorystream;              begin               instream := tmemorystream.create;               outstream := tmemorystream.create;               try                 instream.writecomponentres(pvclass.classname, pvclass);                 //instream.writecomponent(pvclass);                 instream.position := 0;                objectresourcetotext(instream, outstream);                // objectbinarytotext(instream,outstream);                 outstream.position := 0;                 setlength(result,outstream.size+1);                 fillchar(result[1],outstream.size+1,0);                 outstream.readbuffer(result[1],outstream.size);                               freeandnil(instream);                 freeandnil(outstream);               end;             end;             function strtoclass(pvstr:ansistring;pvcomponent:tcomponent):tcomponent;             var               instream, outstream: tmemorystream;             begin               instream := tmemorystream.create;               outstream := tmemorystream.create;               try                 if (pvstr<>'')                 instream.writebuffer(pvstr[1],length(pvstr));                 instream.position:=0;                 objecttexttoresource(instream, outstream);                // objecttexttobinary(instream,outstream);                 outstream.position:=0;                 result:=outstream.readcomponentres(pvcomponent); //*****exception fired*****                 //result:=outstream.readcomponent(pvcomponent);                               freeandnil(instream);                 freeandnil(outstream);               end;              end;              =============             //test             procedure tform1.btn5click(sender: tobject);             var               lvobj,lv1: tsetting;               lvstr:string;               lvarr:tarrayofinteger;             begin               lvobj := tsetting.create(nil);               try                 lvobj.intval := 12345;                 setlength(lvarr, 3);                 lvarr[0] := 222;                 lvarr[1] := 333;                 lvarr[2] := 444;                 lvobj.intarr:=lvarr;                 lvstr:=classtostr(lvobj);                 registerclass(tsetting);                 lvobj.intval:=1;                 lv1:=tsetting( strtoclass(lvstr,lvobj));                 if (lv1.intval>0)                 mmo1.text:=lvstr;                               freeandnil(lvobj);               end;               // writecomponentresfile(extractfilepath(paramstr(0))+ 'd.res',self);             end;              //first chance exception @ $77925b68. exception class ereaderror message 'property  not exist'. process project1.exe (23512)              //first chance exception @ $77925b68. exception class ereaderror message 'error reading tsetting.: property  not exist'. process project1.exe (23512)   result:=outstream.readcomponentres(pvcomponent); //*****exception fired*****

you not allocating array when reading it. so:

procedure tsetting.readintarr(reader: treader); begin   fintarr := nil;   reader.readlistbegin;   while not reader.endoflist begin     setlength(fintarr, length(fintarr) + 1);     fintarr[high(fintarr)] := reader.readinteger;   end;   reader.readlistend; end;

the other change need make move intarr public property. cannot have published, , define property same name in defineproperties.

i dubious of use of ansistring. have expected utf-8 encoded bytes in case of non-ascii characters. perhaps should using string stream appropriate encoding specified.

personally rather sceptical of using form streaming in way. prefer use standard format such json.


Comments

Post a Comment

Popular posts from this blog

java - Run spring boot application error: Cannot instantiate interface org.springframework.context.ApplicationListener -

-
i have spring project , try make use spring boot , run @ embadded tomcat following : https://spring.io/guides/gs/rest-service/ this application //@configuration //@enableaspectjautoproxy @springbootapplication @componentscan(basepackages = "gux.prome") public class application { public static void main(string[] args) { springapplication.run(application.class, args); } } if use maven command: mvn spring-boot:run , project starts fine, need debug , run main method @ intelij, exception occurs: exception in thread "main" java.lang.illegalargumentexception: cannot instantiate interface org.springframework.context.applicationlistener : org.springframework.boot.logging.classpathloggingapplicationlistener @ org.springframework.boot.springapplication.createspringfactoriesinstances(springapplication.java:414) @ org.springframework.boot.springapplication.getspringfactoriesinstances(springapplication.java:394) @ org.springframework.bo...
Read more

python - pip wont install .WHL files -

-
when try install .whl gohike typing cmd c:\users\owner\downloads>pip install ta_lib-0.4.9-cp27-none-win_amd64.whl i print out: `processing c:\users\owner\downloads\ta_lib-0.4.9-cp27-none-win_amd64.whl complete output command python setup.py egg_info: traceback <most recent call last>: file "<string>", line 1, in <module> ioerror: [errno 2] no such file or directory:'c:\\users\\owner\\appdata\\lo cal\\temp\\pip-9gwk2c-build\\setup.py' ----------------------------------------- command "python setup.py egg_info" failed error code 1 in c:\users\owner\ap pdata\local\temp\pip-9gwk2c-build\` the part between pip- , -build in pip-9gwk2c-build different on same file. i asked python 2.7.11 pip 8.0.3 can't install gohike whl of ta-lib 0.4.9 few days ago , decided ask differently. can me! you have outdated pip not understand wheels. wheels not supposed have setup.py inside. try upgrading pip pip in...
Read more

Excel VBA "Microsoft Windows Common Controls 6.0 (SP6)" Location Changes -

-
i have excel workbook used generate quotations customers. there main page user inputs data, , there buttons generate various pdfs , send them customer. however, 1 user consistently getting error preventing generating , sending pdfs. i beleive "microsoft windows common controls 6.0 (sp6)". it's installed on users' computers. on mine, location "c:\windows\syswow64\mscomctl.ocx" on others "c:\windows\system32\mscomctl.ocx" the user experiencing issues on 32-bit machine, "mscomctl.ocx" file should in system32. have manually put in there, , pointed common controls reference in vba it. issue seems keep reverting looking in syswow64. since folder doesn't exist, can't find it, , can't produce pdfs. i thought perhaps issue user running older version of office (2007) there users on 2013 , 2016. thought perhaps mixture of 64-bit , 32-bit users. user gets sent workbook other users (as quotation process goes further, gets passed ...
Read more