Random string from array

Question

I cannot define a string array for unknown reasons on C++. I need to randomly get a string from this array.

Been trying the following:

string bands[] = { "Rammstein", "Slipknot", "Franz Ferdinand", "Gorillaz" };

I'm getting the following as error:

error C2146: syntax error : missing ';' before identifier 'bands'
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C3845: 'SpurdoSparde::Form1::bands': only static data members can be initialized inside a ref class or value type

Just a reminder, I'm using a Windows forms applications. Not sure if it makes any difference whatsoever.

Unrelated to your problem: You should use an `std::vector` instead of a `[]` array. — us2012, Feb 05 '13 at 16:42
Make sure you have `#include ` and prefix `string` with `std::` as in `std::string bands[]] = {...}` — dchhetri, Feb 05 '13 at 16:43

score 2 · Accepted Answer · answered Feb 05 '13 at 16:43

2

It seems you are not including string and/or not using std::string. The following works:

#include <string>

int main()
{
  std::string bands[] = { "Rammstein", "Slipknot", "Franz Ferdinand", "Gorillaz" };
}

If you are after a dynamically sized collection of strings, you should prefer std::vector<std::string> over a C-style array. If you need fixed size, have a look at std::array<std::string, N> or tr1 or boost alternatives if you don't have C++11.

answered Feb 05 '13 at 16:43

juanchopanza

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I did include it from the beginning, and then again, I'm using a forms application rather than a command line, so the `int main()` does not apply, I suppose. – P1C Unrelated Feb 05 '13 at 17:04
1

@P1CUnrelated `main()` is irrelevant here, it could have been any function. – juanchopanza Feb 05 '13 at 17:05

score 1 · Answer 2 · answered Feb 05 '13 at 16:43

1

You either didn't include #include <string> or need to add the std:: namespace qualifier to your type:

std::string bands[] = { ... };

Prefer this over doing using namespace std;.

Also, you ~~might~~ should prefer to use a std::vector rather than a plain old C-style array:

std::vector<std::string> bands = { ... };

answered Feb 05 '13 at 16:43

Joseph Mansfield

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As of your example, I got the following: `error C2039: 'vector' : is not a member of 'std' error C2143: syntax error : missing ';' before '<' error C4430: missing type specifier - int assumed. Note: C++ does not support default-int error C2334: unexpected token(s) preceding '{'; skipping apparent function body` Sorry about the formatting, it's really weird for me. – P1C Unrelated Feb 05 '13 at 16:48
vector literal is not quite like that (yet): http://stackoverflow.com/questions/758118/c-vector-literals-or-something-like-them – thang Feb 05 '13 at 16:49
@P1CUnrelated you need `#include `. Go to http://en.cppreference.com and search for "vector". – juanchopanza Feb 05 '13 at 16:50
My bad, I fixed that before posting, but regardless, `'HorseRacing::Form1::bands': only static data members can be initialized inside a ref class or value type`, and `cannot define 'bands' as a member of managed 'HorseRacing::Form1': mixed types are not supported`. It's really weird, I have done this before. – P1C Unrelated Feb 05 '13 at 16:51
1

It's perfectly fine in C++11. It uses `std::vector::vector(std::initializer_list init, const Allocator& alloc = Allocator() );`. – Joseph Mansfield Feb 05 '13 at 17:07
@thang well, if you replace the `...` by `"hello", "world"` then it should work. I see no reason it wouldn't work in C++11. – juanchopanza Feb 05 '13 at 17:07
@juanchopanza, that's c++0x isn't it? try changing to c++: http://ideone.com/lr4zaB – thang Feb 05 '13 at 17:15
I suspect this is actually the issue that OP is having with his compile error. – thang Feb 05 '13 at 17:21
2

@thang C++0x is just what C++11 was called when they expected it to be standardized before 2010. C++ on ideone is C++03. – Joseph Mansfield Feb 05 '13 at 17:21
@sfrabbit, you're right. forgot it went through. although i think op is using visual studio (or borland?), so he's seeing the same error... – thang Feb 05 '13 at 17:22
@thang it is C++11, which is now C++. The `vector` initialization shown is completely correct according to the current standard. So, it works in C++, it does not work in C++03. – juanchopanza Feb 05 '13 at 17:23

Random string from array

2 Answers2