Boxing and Unboxing

Boxing: The process of converting a value type instance to a reference type instance (This causes the value to be stored on Heap)

Unboxing: The process of converting a reference type instance to a value type instance

// Boxing
int num = 10;
object obj = num;
 
// Unboxing
object obj = 10;
int num = (int)obj;

Info

• Performing Boxing and Unboxing has a small performance hit associated
• If a method takes a reference type value as input and we pass instance type value then boxing will occur (This should be avoided whenever possible)