string manipulation problem

in Basic language I would program this line of code to remove a bit of data from a string and create a new string:

dstring = MID$(sstring, start, n)

is there a comperable method of doing this with the C or C++ language?

I have searched and searched to no avail.

Thanks

You want the std::string class. It has a substr member function.

Code:

# include <string>
using namespace std;

int main()
{
    string source = "abcdefg";

    // should put "ab" into dest. The first parameter is
    // the start index, and the second is the length of
    // the substring
    string dest = source.substr(1,2);

    return 0;
}

IfYouSaySo posted the best solution, but if you want to do it with char arrays instead of STL strings, here's a little function I just whipped up:

Code:

char* sub_copy(const char *source, char *dest, int index, int count) {
  char *p = dest;
  for (; count > 0; --count) {
    *p = source[index++];
    ++p;
  }
  return dest;
}

Originally Posted by IfYouSaySo

You want the std::string class. It has a substr member function.

Code:

# include <string>
using namespace std;

int main()
{
    string source = "abcdefg";

    // should put "ab" into dest. The first parameter is
    // the start index, and the second is the length of
    // the substring
    string dest = source.substr(1,2);

    return 0;
}

source.substr(1,2) will give you "bc", source.substr(0,2) will give you "ab". Indices are zero based.