STL String and member funcs

I'm new to the STL string (all of STL for that matter). I just learned that a NULL string can't be assigned in the copy constructor, and since I'm still getting errors, I'm guessing in the operator = as well. Is there any way to check if I'm going to be assigning a NULL string to another string? I tried

if(name=="") return;
else file = name;

but it didn't really work (name had an address of 0xdddddddd). What can I do? Any help or a website I could find would be appreciated.

Use the strcmp() function from the <cstring> header. For example:

Code:

---

#include <cstring>
#include <string>
using namespace std;

int main()
{
    string file;
    char* name = "Some string.";

    if(strcmp(name, "") == 0)
        return 0;
    else
        file = name;
}

---

Sorry, I wasn't clear. In this code

if(name=="") return;
else file = name;

both name and file are strings. Is there some way to check if name is NULL?

To get the length you can use strings length member function -

if(name.length()==0) return;
else file = name;