如何用它的名称实例化一个类？提前阅读我的文字...... [英] How can I instantiate a class with it's name? read my text ahead...
问题描述
大家好：D
我有一个包含类名的字符串。
我想从该类中实例化：< br $>
string strategyNameStr;
策略*策略;
//以下所有类都来自策略。
//和" strategyNameStr"""包含以下类之一的
之一的名称。
//例如
strategyNameStr = _T（" SimpleStrategy"）;
SimpleStrategy * simStrategy;
MiddleStrategy * midStrategy;
HighStrategy * highStrategy;
如何我可以使用" strategyNameStr"""在下一行......
策略=新的？
或
有没有解决方案？
谢谢。
ba ******** @ yahoo.com 写道：
我有一个包含名称的字符串一个班级。
我想从该班级实例化：
string strategyNameStr;
策略*策略;
//以下所有类都来自策略。
//和" strategyNameStr"""包含以下类之一的
之一的名称。
//例如
strategyNameStr = _T（" SimpleStrategy"）;
SimpleStrategy * simStrategy;
MiddleStrategy * midStrategy;
HighStrategy * highStrategy;
如何我可以使用" strategyNameStr"""在下一行......
策略=新的？
或
有什么解决方案吗？
#define INSTANTIATE_BY_NAME（var，str，clazz）\
if（str == #clazz）var = new clazz
策略= 0;
INSTANTIATE_BY_NAME（策略，strategyNameStr，SimpleStrategy）;
if（！strategy）
INSTANTIATE_BY_NAME（策略，strategyNameStr，MiddleStrategy）;
if（！策略）
INSTANTIATE_BY_NAME（策略，策略名称，高级策略）;
或类似的东西。
V
-
请在回复时删除资金''A'通过电子邮件
我没有回复最热门的回复，请不要问
2007-12-12 15 ：48：47-505，Victor Bazarov < v。******** @ comAcast.netsaid：
>
#define INSTANTIATE_BY_NAME（var，str ，clazz）\
if（str == #clazz）var = new clazz
你不需要Java-拼写错误的类型。
预处理器不关心关键字。
-
Pete
Roundhouse咨询有限公司（ www.versatilecoding.com ）
的作者
标准C ++库扩展：教程和参考
（ www.petebecker.com/tr1book ）
Pete Becker写道：
在2007-12-12 15:48:47 -0500，Victor Bazarov
< v。******** @ comAcast.netsaid：
< blockquote class =post_quotes>
>>
#define INSTANTIATE_BY_NAME（var，str，clazz）\
if（str == #clazz）var = new clazz
你不需要Java拼写错误的拼写错误。
预处理器并不关心关键字。
我的编辑器。
V
-
请在通过电子邮件回复时删除资金''A'
我没有回复最热门的回复，请不要问
Hi everybody:D
I''ve a string that contains the name of a class.
I want to instantiate from that class:
string strategyNameStr;
Strategy * strategy;
// All of the following classes are derived from Strategy.
// and """ strategyNameStr """ contains the name of one of the
following classes.
// e.g.
strategyNameStr = _T( "SimpleStrategy" );
SimpleStrategy * simStrategy;
MiddleStrategy * midStrategy;
HighStrategy * highStrategy;
How can I use """ strategyNameStr """ in the next line...
strategy = new ?
or
Is there at all any solution?
Thanks.
ba********@yahoo.com wrote:I''ve a string that contains the name of a class.
I want to instantiate from that class:
string strategyNameStr;
Strategy * strategy;
// All of the following classes are derived from Strategy.
// and """ strategyNameStr """ contains the name of one of the
following classes.
// e.g.
strategyNameStr = _T( "SimpleStrategy" );
SimpleStrategy * simStrategy;
MiddleStrategy * midStrategy;
HighStrategy * highStrategy;
How can I use """ strategyNameStr """ in the next line...
strategy = new ?
or
Is there at all any solution?#define INSTANTIATE_BY_NAME(var, str, clazz) \
if (str == #clazz) var = new clazz
strategy = 0;
INSTANTIATE_BY_NAME(strategy, strategyNameStr, SimpleStrategy);
if (!strategy)
INSTANTIATE_BY_NAME(strategy, strategyNameStr, MiddleStrategy);
if (!strategy)
INSTANTIATE_BY_NAME(strategy, strategyNameStr, HighStrategy);
or something like that.
V
--
Please remove capital ''A''s when replying by e-mail
I do not respond to top-posted replies, please don''t ask
On 2007-12-12 15:48:47 -0500, "Victor Bazarov" <v.********@comAcast.netsaid:
>
#define INSTANTIATE_BY_NAME(var, str, clazz) \
if (str == #clazz) var = new clazz
You don''t need that Java-esque ugliness of misspelling class. The
preprocessor doesn''t care about keywords.
--
Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)
Pete Becker wrote:On 2007-12-12 15:48:47 -0500, "Victor Bazarov"
<v.********@comAcast.netsaid:>>
#define INSTANTIATE_BY_NAME(var, str, clazz) \
if (str == #clazz) var = new clazz
You don''t need that Java-esque ugliness of misspelling class. The
preprocessor doesn''t care about keywords.My editor does.
V
--
Please remove capital ''A''s when replying by e-mail
I do not respond to top-posted replies, please don''t ask
这篇关于如何用它的名称实例化一个类？提前阅读我的文字......的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
