Delphi应用程序配置的最佳方法是什么？ [英] What is the best way to serialize Delphi application configuration?

问题描述

我会自己回答这个问题，但如果你比我快，或者不喜欢我的解决方案，请随时提供你的答案。我只是想出了这个想法，并希望对此有一些看法。

目标：可读的配置类（如INI文件），但无需编写（并在添加新配置项后调整）加载和保存方法。

我想创建一个类，如

  TMyConfiguration = class（TConfiguration）
 ... 
属性ShowFlags：Boolean读取FShowFlags写入FShowFlags; 
属性NumFlags：整数读取FNumFlags写入FNumFlags; 
结束
  

调用TMyConfiguration.Save（继承自TConfiguration）应该创建一个像

  [选项] 
 ShowFlags = 1 
 NumFlags = 42 
  

问题：最好的方法是什么？

解决方案

这是我提出的解决方案。

我有一个基础课程

  TConfiguration = class 
 protected 
 type 
 TCustomSaveMethod = function（Self：TObject; P：Pointer）：String; 
 TCustomLoadMethod = procedure（Self：TObject; const Str：String）; 
 public 
程序保存（const FileName：String）; 
程序加载（const FileName：String）; 
结束
  

加载方法看起来像这样（相应地保存方法）：

 程序TConfiguration.Load（const FileName：String）; 
 const 
 PropNotFound ='_PROP_NOT_FOUND_'; 
 var 
 IniFile：TIniFile; 
计数：整数; 
列表：PPropList; 
 TypeName，PropName，InputString，MethodName：String; 
 LoadMethod：TCustomLoadMethod; 
 begin 
 IniFile：= TIniFile.Create（FileName）; 
 try 
计数：= GetPropList（Self.ClassInfo，tkProperties，nil）; 
 GetMem（List，Count * SizeOf（PPropInfo））; 
 try 
 GetPropList（Self.ClassInfo，tkProperties，List）; 
 for I：= 0 to Count-1 do 
 begin 
 TypeName：= String（List [I] ^。PropType ^ .Name）; 
 PropName：= String（List [I] ^。Name）; 
 InputString：= IniFile.ReadString（'Options'，PropName，PropNotFound）; 
 if（InputString = PropNotFound）then 
继续; 
 MethodName：='Load'+ TypeName; 
 LoadMethod：= Self.MethodAddress（MethodName）; 
如果没有分配（LoadMethod）然后
 raise EConfigLoadError.Create（'自定义类型的无负载方法'+ TypeName）; 
 LoadMethod（Self，InputString）; 
结束
 finally 
 FreeMem（List，Count * SizeOf（PPropInfo））; 
结束
 finally 
 FreeAndNil（IniFile）; 
结束
  

基类可以为delphi默认类型提供加载和保存方法。然后，我可以为我的应用程序创建一个配置：

  TMyConfiguration = class（TConfiguration）
 ... 
发布
函数SaveTObject（P：指针）：String; 
程序LoadTObject（const Str：String）; 
发布
属性BoolOption：Boolean读取FBoolOption写入FBoolOption; 
属性ObjOption：TObject读取FObjOption写入FObjOption; 
结束
  

自定义保存方法的示例：

  function TMyConfiguration.SaveTObject（P：Pointer）：String; 
 var 
 Obj：TObject; 
 begin 
 Obj：= TObject（P）; 
结果：= Obj.ClassName; //没有意义唯一的例子
结束
  

I will answer this question myself, but feel free to provide your answers if you are faster than me or if you don't like my solution. I just came up with this idea and would like to have some opinions on that.

Goal: a configuration class that is readable (like an INI-file) but without having to write (and adapt after a new configuration item has been added) the load and save methods.

I want to create a class like

TMyConfiguration = class (TConfiguration)
  ...
  property ShowFlags : Boolean read FShowFlags write FShowFlags;
  property NumFlags : Integer read FNumFlags write FNumFlags;
end;

Calling TMyConfiguration.Save (inherited from TConfiguration) should create a file like

[Options]
ShowFlags=1
NumFlags=42

Question: What is the best way to do this?

解决方案

This is my proposed solution.

I have a base class

TConfiguration = class
protected
  type
    TCustomSaveMethod = function  (Self : TObject; P : Pointer) : String;
    TCustomLoadMethod = procedure (Self : TObject; const Str : String);
public
  procedure Save (const FileName : String);
  procedure Load (const FileName : String);
end;

The Load methods look like this (Save method accordingly):

procedure TConfiguration.Load (const FileName : String);
const
  PropNotFound = '_PROP_NOT_FOUND_';
var
  IniFile : TIniFile;
  Count : Integer;
  List : PPropList;
  TypeName, PropName, InputString, MethodName : String;
  LoadMethod : TCustomLoadMethod;
begin
  IniFile := TIniFile.Create (FileName);
  try
    Count := GetPropList (Self.ClassInfo, tkProperties, nil) ;
    GetMem (List, Count * SizeOf (PPropInfo)) ;
    try
      GetPropList (Self.ClassInfo, tkProperties, List);
      for I := 0 to Count-1 do
        begin
        TypeName  := String (List [I]^.PropType^.Name);
        PropName  := String (List [I]^.Name);
        InputString := IniFile.ReadString ('Options', PropName, PropNotFound);
        if (InputString = PropNotFound) then
          Continue;
        MethodName := 'Load' + TypeName;
        LoadMethod := Self.MethodAddress (MethodName);
        if not Assigned (LoadMethod) then
          raise EConfigLoadError.Create ('No load method for custom type ' + TypeName);
        LoadMethod (Self, InputString);
        end;
    finally
      FreeMem (List, Count * SizeOf (PPropInfo));
    end;
  finally
    FreeAndNil (IniFile);
  end;

The base class could provide load and save methods for the delphi default types. I can then create a configuration for my application like this:

TMyConfiguration = class (TConfiguration)
...
published
  function  SaveTObject (P : Pointer) : String;
  procedure LoadTObject (const Str : String);
published
  property BoolOption : Boolean read FBoolOption write FBoolOption;
  property ObjOption : TObject read FObjOption write FObjOption;
end;

Example of a custom save method:

function TMyConfiguration.SaveTObject (P : Pointer) : String;
var
  Obj : TObject;
begin
  Obj := TObject (P);
  Result := Obj.ClassName;  // does not make sense; only example;
end;       

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