REST easy with kbmMW #24 使用kbmMW实现JSON/XML/YAML转换成对象
你想过没有，把一个给定的xml或json生成一个Delphi类，并通过这个类完成对xml或json的读写操作吗？
不管有没有，现在kbmMW为我们实现了，看下面这行代码：
var s:string; ... s:=TkbmMWJSONMarshal.GenerateDelphiClassFromUTF8File('auctions.json','Unit2','JSONData'); ...
{ "realm":{"name":"Aegwynn","slug":"aegwynn"}, "alliance":{"auctions":[ {"auc":1972333274,"item":22574,"owner":"Schäuble","bid":51300,"buyout":54000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":30355200}, {"auc":1970925966,"item":22446,"owner":"Aenni","bid":1890000,"buyout":2450000,"quantity":10,"timeLeft":"LONG","rand":0,"seed":1280052352}, {"auc":1972187088,"item":82800,"owner":"Ainshu","bid":4329000,"buyout":4329000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":955897088,"petSpeciesId":122,"petBreedId":5,"petLevel":1,"petQualityId":2}, {"auc":1972201216,"item":51950,"owner":"Ulath","bid":119157,"buyout":121590,"quantity":3,"timeLeft":"VERY_LONG","rand":0,"seed":1109650432}, ... +60000 entries ]}, "horde":{"auctions":[ {"auc":1970970808,"item":82952,"owner":"Guldarak","bid":4004290,"buyout":4004426,"quantity":1,"timeLeft":"LONG","rand":0,"seed":950078272}, {"auc":1971973942,"item":4306,"owner":"Blutrabé","bid":94500,"buyout":99999,"quantity":20,"timeLeft":"VERY_LONG","rand":0,"seed":956528896}, {"auc":1971973992,"item":4306,"owner":"Blutrabé","bid":94500,"buyout":99999,"quantity":20,"timeLeft":"VERY_LONG","rand":0,"seed":1476867968}, {"auc":1972449149,"item":87893,"owner":"Thêlon","bid":2375000,"buyout":2500000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":848616448}, {"auc":1971763986,"item":74705,"owner":"Gondoline","bid":15558129,"buyout":16662661,"quantity":1,"timeLeft":"LONG","rand":0,"seed":577727872}, ... +2000 entries ]}, "neutral":{"auctions":[ {"auc":1971600068,"item":72145,"owner":"Mellkore","bid":59990000,"buyout":59990000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":436886144}, {"auc":1972336265,"item":8485,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972336316,"item":8487,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972336611,"item":8487,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972336922,"item":8488,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972336986,"item":8488,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1971335148,"item":76085,"owner":"Splatthy","bid":4418750,"buyout":4950000,"quantity":5,"timeLeft":"VERY_LONG","rand":0,"seed":2058173312}, {"auc":1972336837,"item":8487,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972336524,"item":8486,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1971335152,"item":76085,"owner":"Splatthy","bid":4418750,"buyout":4950000,"quantity":5,"timeLeft":"VERY_LONG","rand":0,"seed":2058173312}, {"auc":1972336351,"item":8485,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972386885,"item":4338,"owner":"Huntez","bid":90284,"buyout":95038,"quantity":15,"timeLeft":"VERY_LONG","rand":0,"seed":944449152}, {"auc":1971335163,"item":76085,"owner":"Splatthy","bid":17675000,"buyout":19800000,"quantity":20,"timeLeft":"VERY_LONG","rand":0,"seed":1033557888}, {"auc":1972336774,"item":8487,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1971335155,"item":76085,"owner":"Splatthy","bid":4418750,"buyout":4950000,"quantity":5,"timeLeft":"VERY_LONG","rand":0,"seed":2058173312}, {"auc":1972336383,"item":8485,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972336563,"item":8486,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972386607,"item":12808,"owner":"Huntez","bid":71499,"buyout":79999,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":266490112}, {"auc":1971335149,"item":76085,"owner":"Splatthy","bid":4418750,"buyout":4950000,"quantity":5,"timeLeft":"VERY_LONG","rand":0,"seed":2058173312}, {"auc":1972336707,"item":8486,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972386682,"item":16249,"owner":"Huntez","bid":11250,"buyout":0,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":747154816}, {"auc":1972386894,"item":4338,"owner":"Huntez","bid":90284,"buyout":95038,"quantity":15,"timeLeft":"VERY_LONG","rand":0,"seed":944449152}, {"auc":1972337130,"item":8488,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}, {"auc":1972336425,"item":8485,"owner":"Zaruman","bid":351500,"buyout":450000,"quantity":1,"timeLeft":"VERY_LONG","rand":0,"seed":0}]} }
一行代码，把给定的JSON文件，生成对应的类单元，类名为TJSONData。
将上面的s变量，存在文件，就得到了生成的单元，加入到自己的项目中，就可以通过TJSONData类来访问对应的auctions.json中的内容了！
下面是生成的内容：
unit Unit2; // ========================================================================== // Generated by kbmMW ObjectNotation marshalling converter // 11/03/2019 00:07:12 // ========================================================================== interface uses Classes, Generics.Collections, kbmMWRTTI, kbmMWObjectMarshal, kbmMWDateTime, kbmMWNullable; type TJSONData=class; Trealm=class; Talliance=class; TauctionsList=class; Tauctions=class; Thorde=class; Tneutral=class; [kbmMW_Root('TJSONData',[mwrfIncludeOnlyTagged])] TJSONData=class private Frealm:Trealm; Falliance:Talliance; Fhorde:Thorde; Fneutral:Tneutral; protected procedure Setrealm(const AValue:Trealm); virtual; procedure Setalliance(const AValue:Talliance); virtual; procedure Sethorde(const AValue:Thorde); virtual; procedure Setneutral(const AValue:Tneutral); virtual; public destructor Destroy; override; [kbmMW_Element('realm')] property realm:Trealm read Frealm write Setrealm; [kbmMW_Element('alliance')] property alliance:Talliance read Falliance write Setalliance; [kbmMW_Element('horde')] property horde:Thorde read Fhorde write Sethorde; [kbmMW_Element('neutral')] property neutral:Tneutral read Fneutral write Setneutral; end; [kbmMW_Root('realm',[mwrfIncludeOnlyTagged])] Trealm=class private Fname:kbmMWNullable<string>; Fslug:kbmMWNullable<string>; public [kbmMW_Element('name')] property name:kbmMWNullable<string> read Fname write Fname; [kbmMW_Element('slug')] property slug:kbmMWNullable<string> read Fslug write Fslug; end; [kbmMW_Root('alliance',[mwrfIncludeOnlyTagged])] Talliance=class private Fauctions:TauctionsList; protected procedure Setauctions(const AValue:TauctionsList); virtual; public destructor Destroy; override; [kbmMW_Element('auctions')] property auctions:TauctionsList read Fauctions write Setauctions; end; [kbmMW_Child('auctions',[mwcfFlatten])] TauctionsList=class(TObjectList<Tauctions>); [kbmMW_Root('auctions',[mwrfIncludeOnlyTagged])] Tauctions=class private FpetSpeciesId:kbmMWNullable<double>; FpetBreedId:kbmMWNullable<double>; FpetLevel:kbmMWNullable<double>; FpetQualityId:kbmMWNullable<double>; Fauc:kbmMWNullable<double>; Fitem:kbmMWNullable<double>; Fowner:kbmMWNullable<string>; Fbid:kbmMWNullable<double>; Fbuyout:kbmMWNullable<double>; Fquantity:kbmMWNullable<double>; FtimeLeft:kbmMWNullable<string>; Frand:kbmMWNullable<double>; Fseed:kbmMWNullable<double>; public [kbmMW_Element('petSpeciesId')] property petSpeciesId:kbmMWNullable<double> read FpetSpeciesId write FpetSpeciesId; [kbmMW_Element('petBreedId')] property petBreedId:kbmMWNullable<double> read FpetBreedId write FpetBreedId; [kbmMW_Element('petLevel')] property petLevel:kbmMWNullable<double> read FpetLevel write FpetLevel; [kbmMW_Element('petQualityId')] property petQualityId:kbmMWNullable<double> read FpetQualityId write FpetQualityId; [kbmMW_Element('auc')] property auc:kbmMWNullable<double> read Fauc write Fauc; [kbmMW_Element('item')] property item:kbmMWNullable<double> read Fitem write Fitem; [kbmMW_Element('owner')] property owner:kbmMWNullable<string> read Fowner write Fowner; [kbmMW_Element('bid')] property bid:kbmMWNullable<double> read Fbid write Fbid; [kbmMW_Element('buyout')] property buyout:kbmMWNullable<double> read Fbuyout write Fbuyout; [kbmMW_Element('quantity')] property quantity:kbmMWNullable<double> read Fquantity write Fquantity; [kbmMW_Element('timeLeft')] property timeLeft:kbmMWNullable<string> read FtimeLeft write FtimeLeft; [kbmMW_Element('rand')] property rand:kbmMWNullable<double> read Frand write Frand; [kbmMW_Element('seed')] property seed:kbmMWNullable<double> read Fseed write Fseed; end; [kbmMW_Root('horde',[mwrfIncludeOnlyTagged])] Thorde=class private Fauctions:TauctionsList; protected procedure Setauctions(const AValue:TauctionsList); virtual; public destructor Destroy; override; [kbmMW_Element('auctions')] property auctions:TauctionsList read Fauctions write Setauctions; end; [kbmMW_Root('neutral',[mwrfIncludeOnlyTagged])] Tneutral=class private Fauctions:TauctionsList; protected procedure Setauctions(const AValue:TauctionsList); virtual; public destructor Destroy; override; [kbmMW_Element('auctions')] property auctions:TauctionsList read Fauctions write Setauctions; end; implementation procedure TJSONData.Setrealm(const AValue:Trealm); begin if Assigned(Frealm) then Frealm.Free; Frealm:=AValue; end; procedure TJSONData.Setalliance(const AValue:Talliance); begin if Assigned(Falliance) then Falliance.Free; Falliance:=AValue; end; procedure TJSONData.Sethorde(const AValue:Thorde); begin if Assigned(Fhorde) then Fhorde.Free; Fhorde:=AValue; end; procedure TJSONData.Setneutral(const AValue:Tneutral); begin if Assigned(Fneutral) then Fneutral.Free; Fneutral:=AValue; end; destructor TJSONData.Destroy; begin Frealm.Free; Falliance.Free; Fhorde.Free; Fneutral.Free; inherited; end; procedure Talliance.Setauctions(const AValue:TauctionsList); begin if Assigned(Fauctions) then Fauctions.Free; Fauctions:=AValue; end; destructor Talliance.Destroy; begin Fauctions.Free; inherited; end; procedure Thorde.Setauctions(const AValue:TauctionsList); begin if Assigned(Fauctions) then Fauctions.Free; Fauctions:=AValue; end; destructor Thorde.Destroy; begin Fauctions.Free; inherited; end; procedure Tneutral.Setauctions(const AValue:TauctionsList); begin if Assigned(Fauctions) then Fauctions.Free; Fauctions:=AValue; end; destructor Tneutral.Destroy; begin Fauctions.Free; inherited; end; initialization kbmMWRegisterKnownClasses([TMainClass,Trealm,Talliance,TauctionsList,Tauctions,Thorde,Tneutral]); end.
要实际读取文件，创建一个程序，将Unit2.pas添加到它，并编写以下代码：
procedure TForm1.Button1Click(Sender: TObject); var m:TkbmMWCustomRTTIMarshal; o:TJSONData; begin m:=TkbmMWJSONMarshal.Create; try TkbmMWJSONMarshal(m).AnonymousRoot:=true; o:=TkbmMWJSONMarshal(m).ValueFromUTF8File<TJSONData>('auctions.json'); // Your complete parsed file is now contained in the object instance o. finally o.Free; m.Free; end; end;
下面是一个xml文件：
<?xml version="1.0"?> <root> <course> <reg_num>10577</reg_num> <subj>ANTH</subj> <crse>211</crse> <sect>F01</sect> <title>Introduction to Anthropology</title> <units>1.0</units> <instructor>Brightman</instructor> <days>M-W</days> <time> <start_time>03:10PM</start_time> <end_time>04:30</end_time> </time> <place> <building>ELIOT</building> <room>414</room> </place> </course> <course> <reg_num>20573</reg_num> <subj>ANTH</subj> <crse>344</crse> <sect>S01</sect> <title>Sex and Gender</title> <units>1.0</units> <instructor>Makley</instructor> <days>T-Th</days> <time> <start_time>10:30AM</start_time> <end_time>11:50</end_time> </time> <place> <building>VOLLUM</building> <room>120</room> </place> </course> <course> <reg_num>10624</reg_num> <subj>BIOL</subj> <crse>431</crse> <sect>F01</sect> <title>Field Biology of Amphibians</title> <units>0.5</units> ... </course> ... </root>
把上面xml内容生成类的代码：
var s:string; ... s:=TkbmMWXMLMarshal.GenerateDelphiClassFromFile('courses.xml','Unit3','XMLData'); ...
把s变成存为Unit3.pas文件：
unit Unit3; // ========================================================================== // Generated by kbmMW ObjectNotation marshalling converter // 10/03/2019 23:54:52 // ========================================================================== interface uses Classes, Generics.Collections, kbmMWRTTI, kbmMWObjectMarshal, kbmMWDateTime, kbmMWNullable; type Troot=class; TcourseList=class; Tcourse=class; Ttime=class; Tplace=class; [kbmMW_Root('root',[mwrfIncludeOnlyTagged])] Troot=class private Fcourse:TcourseList; protected procedure Setcourse(const AValue:TcourseList); virtual; public destructor Destroy; override; [kbmMW_Element('course')] property course:TcourseList read Fcourse write Setcourse; end; [kbmMW_Child('course',[mwcfFlatten])] TcourseList=class(TObjectList<Tcourse>); [kbmMW_Root('course',[mwrfIncludeOnlyTagged])] Tcourse=class private Ftime:Ttime; Fplace:Tplace; Freg_num:kbmMWNullable<string>; Fsubj:kbmMWNullable<string>; Fcrse:kbmMWNullable<string>; Fsect:kbmMWNullable<string>; Ftitle:kbmMWNullable<string>; Funits:kbmMWNullable<string>; Finstructor:kbmMWNullable<string>; Fdays:kbmMWNullable<string>; Fxml_repository:kbmMWNullable<string>; protected procedure Settime(const AValue:Ttime); virtual; procedure Setplace(const AValue:Tplace); virtual; public destructor Destroy; override; [kbmMW_Element('time')] property time:Ttime read Ftime write Settime; [kbmMW_Element('place')] property place:Tplace read Fplace write Setplace; [kbmMW_Element('reg_num')] property reg_num:kbmMWNullable<string> read Freg_num write Freg_num; [kbmMW_Element('subj')] property subj:kbmMWNullable<string> read Fsubj write Fsubj; [kbmMW_Element('crse')] property crse:kbmMWNullable<string> read Fcrse write Fcrse; [kbmMW_Element('sect')] property sect:kbmMWNullable<string> read Fsect write Fsect; [kbmMW_Element('title')] property title:kbmMWNullable<string> read Ftitle write Ftitle; [kbmMW_Element('units')] property units:kbmMWNullable<string> read Funits write Funits; [kbmMW_Element('instructor')] property instructor:kbmMWNullable<string> read Finstructor write Finstructor; [kbmMW_Element('days')] property days:kbmMWNullable<string> read Fdays write Fdays; [kbmMW_Element('xml_repository')] property xml_repository:kbmMWNullable<string> read Fxml_repository write Fxml_repository; end; [kbmMW_Root('time',[mwrfIncludeOnlyTagged])] Ttime=class private Fstart_time:kbmMWNullable<string>; Fend_time:kbmMWNullable<string>; public [kbmMW_Element('start_time')] property start_time:kbmMWNullable<string> read Fstart_time write Fstart_time; [kbmMW_Element('end_time')] property end_time:kbmMWNullable<string> read Fend_time write Fend_time; end; [kbmMW_Root('place',[mwrfIncludeOnlyTagged])] Tplace=class private Fbuilding:kbmMWNullable<string>; Froom:kbmMWNullable<string>; public [kbmMW_Element('building')] property building:kbmMWNullable<string> read Fbuilding write Fbuilding; [kbmMW_Element('room')] property room:kbmMWNullable<string> read Froom write Froom; end; implementation procedure Troot.Setcourse(const AValue:TcourseList); begin if Assigned(Fcourse) then Fcourse.Free; Fcourse:=AValue; end; destructor Troot.Destroy; begin Fcourse.Free; inherited; end; procedure Tcourse.Settime(const AValue:Ttime); begin if Assigned(Ftime) then Ftime.Free; Ftime:=AValue; end; procedure Tcourse.Setplace(const AValue:Tplace); begin if Assigned(Fplace) then Fplace.Free; Fplace:=AValue; end; destructor Tcourse.Destroy; begin Ftime.Free; Fplace.Free; inherited; end; initialization kbmMWRegisterKnownClasses([Troot,TcourseList,Tcourse,Ttime,Tplace]); end.
读取和写入这个XML数据的Delphi代码:
procedure TForm1.Button2Click(Sender: TObject); var m:TkbmMWCustomRTTIMarshal; o:Troot; s:string; begin m:=TkbmMWXMLMarshal.Create; try o:=TkbmMWXMLMarshal(m).ValueFromFile<Troot>('courses.xml'); // o now contains all courses. s:=TkbmMWXMLMarshal(m).ValueToString(o); // s now contains XML generated from o. finally o.Free; m.Free; end; end;
