csingleton.pas

来自「Delphi深度探索,Delphi深度探索（第二版）」· PAS 代码 · 共 51 行

unit CSingleton;

interface
type
  TSingleConfig=class(TObject)
  private
    FConfigPath: string;
    procedure SetConfigPath(const Value: string);
  public
    class function GetInstance():TSingleConfig;
    //系统配置路径
    property ConfigPath:string read FConfigPath write SetConfigPath;
    //...省略
    class function NewInstance: TObject; override;    
    procedure FreeInstance;override;
  end;

implementation

var
  GlobalConfig:TSingleConfig=nil;//单元内私有的静态配置对象变量

{ TSingleConfig }

procedure TSingleConfig.FreeInstance;
begin
  inherited;
  GlobalConfig:=nil;
end;

class function TSingleConfig.GetInstance: TSingleConfig;
begin
  if not Assigned(GlobalConfig) then
    GlobalConfig:=TsingleConfig.Create();
  Result:=GlobalConfig;
end;

class function TSingleConfig.NewInstance: TObject;
begin
  if not Assigned(GlobalConfig) then
    GlobalConfig:=TSingleConfig(inherited NewInstance);
  Result:=GlobalConfig;
end;

procedure TSingleConfig.SetConfigPath(const Value: string);
begin
  FConfigPath := Value;
end;

end.