C# LINQ Datetime Between

LINQ (Language Integrated Query) is a powerful feature in C# that allows developers to query data from different data sources (e.g., SQL Server, XML, collection objects) using a unified syntax. When working with datetime values in LINQ, it's often necessary to filter the data based on a range of dates. In this article, we will explore how to use LINQ to filter data based on datetime between two specific dates.

DateTime Between Operator

The DateTime struct in C# has a built-in method called Between that can be used to check whether a datetime value falls between two specific dates. The method takes three parameters: the datetime value to check, the start date, and the end date. Here's the method signature:

public static bool Between(this DateTime dt, DateTime start, DateTime end)

Example Usage

Suppose we have a list of orders with order dates, and we want to retrieve all orders that were placed between January 1, 2020, and December 31, 2020:

List<Order> orders = GetOrders();
DateTime start = new DateTime(2020, 1, 1);
DateTime end = new DateTime(2020, 12, 31);

var filteredOrders = orders.Where(o => o.OrderDate.Between(start, end));

The Where method takes a lambda expression that defines the filter criteria. In this case, we are filtering the orders based on their OrderDate property by calling the Between method with the start and end dates.

Conclusion

Using the Between operator makes it easy to filter datetimes within a specific range in LINQ. Keep in mind that DateTime values are precise to the nearest tick (100 nanoseconds), so when specifying the start and end dates, make sure to provide a time value (e.g., midnight) to ensure that all datetime values within the range are included in the result set.