ERP SYSTEM 开发指南(二)添加脚本支持
在二次开发中实现脚本对算定义类的调用
如何为一个类添加脚本支持,FastScript是解释执行的语言,通过对语义的分析来执行
FastScript已经对Delphi常用的类做好了解释,比如fs_iformsrtti解释了脚本对窗体的调用,fs_iinirtti解释了脚本对TIniFiles类的使用
一个类的published属性,在RTTI的支持下可以自动解释,关键是函数的解释
模拟下面源代码的编写,就可以在脚本中直接使用该类
unit fs_iMyClassRTTI; //按FastScript的习惯命名, fs_类名RTTI.pas interface uses Windows, Messages, SysUtils, StrUtils, Variants, Classes, Graphics, Controls, Forms; type TMyClass=class(TObject) private FNewProp:string; FNewProp2:string; public constructor Create; function Func1(int i):int; function Func2(str:TStrings):boolean; public property NewProp2:string read FNewProp2 write FNewProp2; published property NewProp:string read FNewProp write FNewProp; end; implementation type TFunctions = class(TfsRTTIModule) private private //函数调用 function CallMethod(Instance: TObject; ClassType: TClass; const MethodName: String; Caller: TfsMethodHelper): Variant; //属性获取 function GetProp(Instance: TObject; ClassType: TClass; const PropName: String): Variant; //属性设置 procedure SetProp(Instance: TObject; ClassType: TClass; const PropName: String; Value: Variant); public //在构照器进行类型,函数说明 constructor Create(AScript: TfsScript); override; end; { TMyClass } function TMyClass.Func1(int i):int; begin result:=0; end; function TMyClass.Func2(str:TStrings):boolean; begin result:=True; end; { TFunctions } function TFunctions.CallMethod(Instance: TObject; ClassType: TClass; const MethodName: String; Caller: TfsMethodHelper): Variant; begin Result := 0; //根据函数名调用实际执行的函数,关键当参数为类对象时的转换,看函数Func2的调用写法 if ClassType = TMyClass then begin if MethodName = \'CREATE\' then Result := Integer(TMyClass.Create) else if MethodName = \'FUNC1\' then Result:= TMyClass(Instance).Func1(Caller.Params[0])) else if MethodName = \'FUNC2\' then Result := TMyClass(Instance).Func2(TStrings(Integer(Caller.Params[0]))) end; end; constructor TFunctions.Create(AScript: TfsScript); begin inherited; with AScript do begin //添加类说明,第一个参数为被说明的类,第二个参数为该类型的基类 with AddClass(TMyClass, \'TObject\') do begin //添加函数定义说明,第二个参数是该函数由哪个函数调用 AddMethod(\'function Func1(int i):int;\',CallMethod); AddMethod(\'function Func2(str:TStrings):boolean;\',CallMethod); end; end; end; function TFunctions.GetProp(Instance: TObject; ClassType: TClass; const PropName: String): Variant; begin //添加属性说明,published属性不必添加 if ClassType = TMyClass then begin if PropName = \'NewProp2\' then Result := TMyClass(Instance).NewProp2; end end; procedure TFunctions.SetProp(Instance: TObject; ClassType: TClass; const PropName: String; Value: Variant); begin if ClassType = TMyClass then begin if PropName = \'NewProp2\' then TMyClass(Instance).NewProp2:=Value; end end; initialization //文件加载时,将解析类TFunctions添加到脚本引擎RTTI库 fsRTTIModules.Add(TFunctions); finalization fsRTTIModules.Remove(TFunctions);