how can this be implement?

[Lordaeron]

class data:public baseData
{
public:
int aaa;
char bbb[3];
int ccc;
}
now i want a function something like
get(1) return values of aaa;
get(2) return values of bbb;
set(1,30) set the values of aaa to 30;
and because the data class may have different content,
and i think, i don't want to write N times of get and set, the
data may have data1, data2 .... etc, so , is there anyway that
can easier to implement.
i think i am doing something like Resultset of Java

[Victor Bazarov]

Re: how can this be implement?

"Lordaeron" <lordaeron@ms1. url.com.tw> wrote...[color=blue]
> class data:public baseData
> {
> public:
> int aaa;
> char bbb[3];
> int ccc;
> }
> now i want a function something like
> get(1) return values of aaa;
> get(2) return values of bbb;
> set(1,30) set the values of aaa to 30;
> and because the data class may have different content,
> and i think, i don't want to write N times of get and set, the
> data may have data1, data2 .... etc, so , is there anyway that
> can easier to implement.[/color]

No.
[color=blue]
> i think i am doing something like Resultset of Java[/color]

Then don't do it. Or use Java.

Victor

[John Harrison]

Re: how can this be implement?


"Lordaeron" <lordaeron@ms1. url.com.tw> wrote in message
news:5830ddda.0 307140206.5b34b 876@posting.goo gle.com...[color=blue]
> class data:public baseData
> {
> public:
> int aaa;
> char bbb[3];
> int ccc;
> }
> now i want a function something like
> get(1) return values of aaa;
> get(2) return values of bbb;
> set(1,30) set the values of aaa to 30;
> and because the data class may have different content,
> and i think, i don't want to write N times of get and set, the
> data may have data1, data2 .... etc, so , is there anyway that
> can easier to implement.
> i think i am doing something like Resultset of Java[/color]

You would have to derive all your data types from a common base class. Then
you'd probably want to add a smart pointer class to handle the memory
allocation. And you'd need to do RTTI to get at the actual underlying data.

It's a nightmare, don't do it, or do it in Java. Don't fight the language.

john

[Glen Low]

Re: how can this be implement?

> class data:public baseData[color=blue]
> {
> public:
> int aaa;
> char bbb[3];
> int ccc;
> }
> now i want a function something like
> get(1) return values of aaa;
> get(2) return values of bbb;
> set(1,30) set the values of aaa to 30;[/color]

[snipped]
[color=blue]
> i think i am doing something like Resultset of Java[/color]

If you can be happy with declaring data that you don't know the type
of, like in an ADO Recordset, you may want to try boost::any, see
http://www.boost.org or http://www.boost.org/doc/html/ch01s02.html.

Then you can say
typedef boost::any data [n]; // for fixed number of fields, or
typedef std::vector <boost::any> data; // for variable number of
fields.