用map实现反射的简单例子。
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#include <iostream>
#include <string>
#include<map>
using
namespace
std;
class
Base
{
public
:
virtual
void
say()=0;
};
class
A:
public
Base
{
public
:
virtual
void
say()
{
cout<<
"This is A"
<<endl;
}
};
class
B:
public
Base
{
public
:
virtual
void
say()
{
cout<<
"This is B"
<<endl;
}
};
template
<
typename
T>
Base *Create()
//创建函数
{
return
new
T;
}
typedef
Base*(*FUN)();
map<string, FUN> rmap;
//由类名到创建函数的映射
int
main()
{
rmap[
"A"
]=Create<A>;
//注册
rmap[
"B"
]=Create<B>;
//注册
string str=
"A"
;
Base* p=rmap[str]();
//动态创建
p->say();
delete
p;
str=
"B"
;
p=rmap[str]();
//动态创建
p->say();
delete
p;
}
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