LINQ Interview Question #69
What does Intersect do in LINQ?
Joins, Grouping, Set & Quantifier Operators Mid-Level Intermediate
Quick Interview Answer
Intersect returns distinct elements that appear in both sequences. Equality comparison determines whether elements match.
Detailed Explanation
Intersect returns distinct elements that appear in both sequences. Equality comparison determines whether elements match.
It is useful for finding shared IDs, permissions, tags, categories, or other values between two sets.
Code Example
var requested = new[] { 1, 2, 3, 4 };
var allowed = new[] { 2, 4, 6 };
var result = requested.Intersect(allowed);
// 2, 4