GC>    Recently, I want to use Borland C++ 4.0 to write a oop program. When I

 GC> tried to initialize a pointer of array of structure with a series of data,

 GC> the compiler does not permit that. The pointer is a data member of a class,

 GC> the compiler told me to use something like constructor to do it. But I

 GC> don't know how. Can you help me? :)



 GC> the program look likes this:



 GC> struct unit {char ch;int i};



 GC> class dim

 GC> {

 GC>   unit *x;

 GC> };



 GC> x=new unit[]={...};





Suggestion: Before you give us a problem, try to write a tiny

compilable program that clearly demonstrates the problem. Often,

you'll find the solution yourself while you do this.



And if that doesn't work, the tiny compilable program is MUCH

easier for us alleged experts to troubleshoot...





The following mess compiles ok under BC++4.02, and shows a couple

of ways of initializing class data.



====



struct Unit { char ch; int i; };



class Dim1  /* this class doesn't define a constructor, it uses C++'s default

               constructor (with no parameters)*/

{

  public:   // optional. But if omitted, all members will be PRIVATE!



    Unit x;              // data member

    void setch(char C);  // public member functions for setting data members

    void seti (int I);

};



class Dim2  // this class uses a constructor that initializes the class's data

{

  public:

    Unit x;              // data member

    Dim2(char C, int I); // constructor with parameters

};



// fully define the class functions here



void Dim1::setch(char C)  {x.ch = C;}

void Dim1::seti (int I)   {x.i = I;};



Dim2::Dim2(char C, int I) {x.ch = C;  x.i  = I;}





// this is the real program



int main(void)

{

 /* Define a class, and a pointer to a class, for both Dim1 and Dim2.



     Note the Dim2 variable definition "realdim2" contains the
intial x values

     in its constructor, but the Dim2 pointer definition doesn't - this is

     because dpointer2 is only a pointer, so it ain't got no room for the

     contents of class Dim2. The contents happen later, when "new
Dim2('d',4)"

     is called. */



 Dim1  realdim1;         // this is a real occurrence of Dim1

 Dim2  realdim2('c', 3); /* this is a real Dim2,

                            and it's initialized with 'c' and 3 */



 Dim1  *dpointer1;       // this is only a pointer to a not yet real Dim1

 Dim2  *dpointer2;       // ditto for Dim2



 realdim1.x.ch = 'a';    // initialize data members of Dim1 directly

 realdim1.x.i  = 1;

                         // Or alternatively,

 realdim1.setch('b');    // call Dim1's set-data functions. Useful if you

 realdim1.seti(2);       // want ch and i to be private members of class Dim1.



 dpointer1 = new Dim1;   // Create a new Dim1, pointed to by dpointer1

 dpointer1->x.ch = 'b';  // and initialize its data members directly.

 dpointer1->x.i = 2;



 dpointer2 = new Dim2('d', 4); /* Create (and initialize the data

                                  member of) a new Dim2. */

return 1;

}



====



Cheers





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