Question

Possible Duplicate:
Modifying a C string: access violation

int main()
    {   
        char str_1[7] = "string";
        char* str_2 = new char[7];
        str_2 = "string";
        str_1[2] = 'a'; //ok
        str_2[2] = 'a'; //error

        return 0;
    }

i get “access violation” error here str_2[2] = 'a';
I don’t understand why i can’t access dynamic string via index here? (VS2010) Thanks.

Answer 1

You can not assign to a string like you do. Instead of copying the strings contents you copy the pointer. Thus str_2 now points to a string literal and can not be modified. To copy string’s contents use strcpy.

Even worse- in your version of the code there is a memory leak for the memory allocated for str_2 in the line where you call new.