Using LINQ to Extract Unique Car Objects Based on CarCode

Managing collections of objects with potentially redundant properties often requires efficient filtering techniques. This article demonstrates how LINQ simplifies the process of retrieving distinct objects from a collection, focusing on uniqueness based on a specific property.

The Challenge:

Suppose you have a list of Car objects, each uniquely identified by its CarCode property. The task is to use LINQ to create a new collection containing only cars with unique CarCode values.

The Solution:

LINQ's grouping and selection capabilities provide a concise solution:

List cars = new List();
List distinctCars =
  cars
  .GroupBy(car => car.CarCode)
  .Select(g => g.First())
  .ToList();

Detailed Explanation:

The GroupBy method organizes the original cars list into groups, categorized by the CarCode property. Each group contains cars sharing the same CarCode.

Subsequently, the Select method iterates through these groups, selecting the first Car object from each. Since each group represents a unique CarCode, this selection ensures that the resulting collection contains only distinct Car objects.

The ToList() method converts the resulting sequence into a new List, distinctCars, containing only cars with unique CarCode values. This effectively eliminates duplicate car objects based on their identifying code.