Reversing a string without creating extra memory

Question

I have a string which is of about 1mb size. The requirement is to reverse the string without allocating another temp string of size 1 MB. I tried the following code

string name = "abcde";

string target = "";
for(int i = name.Length - 1; i >=0; i--)
{
    target += name[i];
    name = name.Remove(i);                
    int n = name.Length;
}

but my friend says if we use the function name.Remove(i) it will return a new string but it is not guaranteed that the old string will be deleted from memory and so there is no guarantee that the size will be reduced. is it true? if so is there any other option available to reverse a string without allocating extra memory?

Answer 1

Your string "abcde" is a constant in memory. You can't change it, as it is immutable. What you want is to create a new string, and for this you need new memory.

Answer 2

use StringBuilder you can manupulate with char array, but not with string, bacause it's immutable