有没有一个好的方法来设置C / C ++成员变量从字符串表示？ （内省） [英] Is there a good way of setting C/C++ member variables from string representations? (introspection-lite)

问题描述

我有一个结构体有一些成员，我想能够从一个字符串获取和设置。由于C ++没有任何内省我需要一些创造性的解决方案与宏，stringize运算符和可能 boost :: bind。我不需要完全序列化或

I've got a struct with some members that I want to be able to get and set from a string. Given that C++ doesn't have any introspection I figure I need some creative solution with macros, the stringize operator and maybe boost::bind. I don't need full serialization or introspection, more an 'introspection-lite'

我想要有这样的东西：

struct MyType {
  int  fieldA;
  int  fieldB;
};
DECLARE_STRING_MAP(MyType,fieldA);
DECLARE_STRING_MAP(MyType,fieldB);

MyType t;
SET_VALUE_FROM_STRING(MyType,t,"fieldA","3")

一个巨大的 if 语句。

任何想法如果有一个整洁的解决方案？

Any idea if there's a neat solution to this?

相关问题： http://stackoverflow.com/questions/1540114/object-reflection

编辑：
感谢maxim1000的'map to int Type :: *'技巧 - 这对我有用：

Thanks to maxim1000 for the 'map to int Type::*' trick -- this worked for me:

#define DEFINE_LOOKUP_MAP(Type) std::map<AnsiString,int Type::*> mapper 
#define ADD_FIELD_MAPPING(Type, Field) mapper[#Field]=&Type::Field 
#define SET_FIELD_FROM_MAP(Type, Field, var, value) var.*(mapper[#Field])=value    

DEFINE_LOOKUP_MAP(MyType); 
ADD_FIELD_MAPPING(MyType, fieldA); 
ADD_FIELD_MAPPING(MyType, fieldB); 

SET_FIELD_FROM_MAP(MyType, fieldA, obj, 3);

推荐答案

如果所有的类型都相同，使用这样的：

If all of them have the same type, you can use something like this:

std::map<std::string,int MyType::*> mapper;
mapper["fieldA"]=&MyType::fieldA;
mapper["fieldB"]=&MyType::fieldB;
...
MyType obj;
obj.*(mapper["fieldA"])=3;

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