#273 – Parameter Modifier Summary

Here’s a summary of the different parameter modifiers and how the behavior changes for each, when using them with value-typed and reference-typed variables.

• No modifier – value types
  • Copy of value passed to method
  • Method can read value
• No modifier – reference types
  • Reference to object passed to method
  • Method can read/write object contents
• ref modifier – value types
  • Reference to variable passed to method
  • Method can read/write variable
• ref modifier – reference types
  • Reference to object reference passed to method
  • Method can read/write object contents
  • Method can change reference to point to new object
• out modifier – value types
  • Reference to variable passed to method
  • Method must write new value to variable
• out modifier – reference types
  • Reference to object reference passed to method
  • Method must change reference to point to new object