C# How to get reference type behaviour with String?

Question

This question came to me with this common code sample frecuently used to explain difference between value types and reference types:

class Rectangle
{
    public double Length { get; set; }
}

struct Point 
{
    public double X, Y;
}

Point p1 = new Point();
p1.X = 10;
p1.Y = 20;
Point p2 = p1;
p2.X = 100;
Console.WriteLine("p1.X = {0}", p1.X);

Rectangle rect1 = new Rectangle
{ Length = 10.0, Width = 20.0 };
Rectangle rect2 = rect1;
rect2.Length = 100.0;
Console.WriteLine("rect1.Length = {0}",rect1.Length);

In this case, the second Console.WriteLine statement will output: “rect1.Length = 100”

In this case class is reference type, struct is value type. How can I demostrate the same reference type behaviour using a string ?

Thanks in advance.

Answer 1

You can't. Strings are immutable.. which means you can't change them directly. Any changes to a string are actually a new string being returned.

Therefore, this (which I assume you mean):

string one = "Hello";
string two = one;

two = "World";

Console.WriteLine(one);

..will print "Hello", because two is now an entirely new string and one remains as it was.