C# Feature - ref returns

Overview

Ref returns allow a method to return an alias to existing storage instead of a copied value.

Introduced In

C# 7.0 (2017)

Example

static ref int Find(int[] data) => ref data[0];

ref int first = ref Find(values);
first++;

Gotchas & Best Practices

• Only return references to storage that outlives the method call.
• Avoid ref returns unless mutation of the original storage is the goal.