C++ Update Struct

Question

I have this:

typedef struct {
    char nome[50];
    char morada[100];
    char codpostal[8];
    char localidade[30];
    int telefone;
    int nContribuinte;
} CLIENTE;
CLIENTE c;

How do I update c.nome like c.nome = "something";? Can't figure out why wouldn't this work... c has already been filled with known info saved on a binary file

I'm supposed to do this: if (Conf == 1) { scanf("%s", c.nome); } else { c = Clt.nome; }

You don't need a `typedef` for `struct`s in c++, you could just name it. — , May 09 '17 at 16:16
In C++ arrays are non assignable, you can use a function to fill it out with your string literal, `strcpy` would work. Just make sure you've enough space for a nul terminator or some serious sadness will occur :-) — George, May 09 '17 at 16:18

score 3 · Accepted Answer · edited May 23 '17 at 11:47

3

For C-like strings, use strcpy(), like this:

strcpy(c.nome, "something");

The reason what you tried didn't work is that you used C-like strings, and not std::string, which is the C++ approach, and has overloaded the assignment operator. In that case your struct would look like this:

#include <string>

struct CLIENTE {
    std::string nome;
    ...
};
CLIENTE c;
c.nome = "something";

You can avoid the typedef, as described in Difference between 'struct' and 'typedef struct' in C++?:

In C++, all struct declarations act like they are implicitly typedef'ed, as long as the name is not hidden by another declaration with the same name.

edited May 23 '17 at 11:47

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answered May 09 '17 at 16:16

gsamaras

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why are you suggesting array of string `std::string nome[50]`. its should be `simply std::string nome`; – danishansari May 09 '17 at 16:19
Leftovers @danishansari, but I could edit my post because it was in the review queue for a suggested edit! Thank you! – gsamaras May 09 '17 at 16:20
typedef is also not required in c++, since you are giving a c++ solution. – danishansari May 09 '17 at 16:21
Oh now I understood what you meant, thank you @danishansari! – gsamaras May 09 '17 at 16:50
That works perfectly! Thanks bud :D About the `typedef` thing. This is a school project, and the teacher want's students to use 20 years old code... `fseek`, `fread`, `fopen`, `fclose`, `printf `, you name it... – C. Carrasquinho May 10 '17 at 10:21
Well maybe he has a reason @C.Carrasquinho ;) – gsamaras May 10 '17 at 10:23
What about the int values? `strcpy` doesn't work for them (edit: Yes I will bud. Done :) ) – C. Carrasquinho May 10 '17 at 10:25
@C.Carrasquinho `strcpy()` is for strings, it means string copy. For integers, just do `c. telefone = 5;` – gsamaras May 10 '17 at 10:26
that made me laugh for some reason xD Thanks again! – C. Carrasquinho May 10 '17 at 10:27

C++ Update Struct

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