Getting array from std:vector

Question

What is the easiest way of getting a char array from a vector?

The way I am doing is getting a string initialized using vector begin and end iterators, and then getting .c_str() from this string. Are there other efficient methods?

Answer 1

This was discussed in Scott Meyers' Effective STL, that you can do &vec[0] to get the address of the first element of an std::vector, and since the standard constrains vectors to having contiguous memory, you can do stuff like this.

// some function void doSomething(char *cptr, int n) {  }  // in your code std::vector<char> chars;  if (!chars.empty()) {     doSomething(&chars[0], chars.size()); } 

edit: From the comments (thanks casablanca)

• be wary about holding pointers to this data, as the pointer can be invalidated if the vector is modified.