How to define an array in a structure?

[CharChen]

How to define an array in a structure?

STRUCT A
{
 B data[];
};

why is this wrong?

[Dy7SLyTq]

try a vector

[MikeyBoy]

why is this wrong?

Because:

(a) the C++ keyword is struct, not STRUCT.

(b) you need to declare the array with its size.

But, as DTSCode says:

try a vector

Vectors are much safer than C-style arrays.

[CharChen]

Well...c++ is much more complicated than c...
Thanks ...

[CharChen]

a friend of mine told me to try defining a pointer in the structure like this:

struct A {            
B*       pdata;          
}; 

and

A a;
a.pData = new B[100];

Is this solution better than vector?

[Dy7SLyTq]

no. well its c++ but then you have to remember to delete it and you still wont have as much as a vector will give you

[CharChen]

well..i failed..
syntax error : missing ';' before '*'

struct A {            
B*       pdata;          
}; 
struct B{
int i;
};

This won't work. I got an error...
but i changed it into

struct A {            
char*       pdata;          
}; 

Then it can be compiled successfully...
why can't the first one be compiled? any syntax error?

[MikeyBoy]

Because you're trying to use the type B before you've declared it.

Since you're only using a pointer to B, you can use a forward declaration:

struct B;

struct A {            
B*       pdata;          
}; 

struct B{
int i;
};