gistfile1.cs

// Reference type (because of 'class')
class SomeRef { public Int32 x; }
// Value type (because of 'struct')
struct SomeVal { public Int32 x; }
static void ValueTypeDemo() {
SomeRef r1 = new SomeRef(); // Allocated in heap
SomeVal v1 = new SomeVal(); // Allocated on stack
Chapter 5 Primitive, Reference, and Value Types 123
r1.x = 5; // Pointer dereference
v1.x = 5; // Changed on stack
Console.WriteLine(r1.x); // Displays "5"
Console.WriteLine(v1.x); // Also displays "5"
// The left side of Figure 5-2 reflects the situation
// after the lines above have executed.
SomeRef r2 = r1; // Copies reference (pointer) only
SomeVal v2 = v1; // Allocate on stack & copies members
r1.x = 8; // Changes r1.x and r2.x
v1.x = 9; // Changes v1.x, not v2.x
Console.WriteLine(r1.x); // Displays "8"
Console.WriteLine(r2.x); // Displays "8"
Console.WriteLine(v1.x); // Displays "9"
Console.WriteLine(v2.x); // Displays "5"
// The right side of Figure 5-2 reflects the situation
// after ALL of the lines above have executed.
}