How can you perform sorting in LINQ?

 In LINQ (Language Integrated Query), you can perform sorting operations on collections using the OrderBy, OrderByDescending, ThenBy, and ThenByDescending methods. These methods allow you to sort the elements of a sequence based on one or more keys.

Here's an overview of how you can perform sorting in LINQ:

1. OrderBy: This method sorts the elements of a sequence in ascending order based on a key.

var sortedList = collection.OrderBy(item => item.Property);

In the above example, collection is the original sequence, item => item.Property is a lambda expression that defines the key to sort on (replace Property with the actual property or field name you want to sort by), and sortedList will contain the sorted sequence.

2. OrderByDescending: This method sorts the elements of a sequence in descending order based on a key.

var sortedList = collection.OrderByDescending(item => item.Property);

The usage is similar to OrderBy, but the elements will be sorted in descending order.

3. ThenBy: This method is used for secondary sorting. It sorts the elements in ascending order based on a second key, after an initial sorting has been performed.

var sortedList = collection.OrderBy(item => item.FirstProperty)
                          .ThenBy(item => item.SecondProperty);

In the above example, the elements are first sorted by FirstProperty, and then for items with the same FirstProperty value, they are sorted by SecondProperty.

4. ThenByDescending: This method is similar to ThenBy, but it performs a secondary sorting in descending order.

var sortedList = collection.OrderBy(item => item.FirstProperty)
                          .ThenByDescending(item => item.SecondProperty);

In this case, the elements are first sorted by FirstProperty, and for items with the same FirstProperty value, they are sorted by SecondProperty in descending order.

Note that the OrderBy, OrderByDescending, ThenBy, and ThenByDescending methods return a new sequence with the sorted elements, and the original collection remains unchanged. If you want to sort the elements in place, you can use the List<T>.Sort method.