What is LINQPad?
Tags: beginners, programming, dotnet, csharp
Published: 2023-03-24 21:43:16

LINQPad is a popular software tool developers use to write and test LINQ (Language-Integrated Query) queries against different data sources. It was first introduced in 2007 and has become a widely-used tool for developers working with .NET-based languages such as C# and VB.NET.

At its core, LINQPad provides a simple and easy-to-use interface for writing and executing LINQ queries. LINQ queries allow developers to interact with data more naturally and intuitively, using a familiar syntax resembling SQL. With LINQPad, developers can write LINQ queries against various data sources, including SQL databases, XML files, and Azure Cosmos DB.

One of the critical features of LINQPad is its ability to provide real-time feedback and results as developers write their queries. This allows developers to quickly iterate on their queries and see the results of their changes without executing the query separately in a different environment. LINQPad also provides various debugging tools, such as the ability to step through queries and view intermediate results, making it an invaluable tool for troubleshooting and optimizing queries.

Another valuable feature of LINQPad is its ability to generate code snippets and sample data for developers. This makes it easier to start with LINQ queries, as developers can quickly generate sample code and data to work with rather than manually creating everything from scratch.

Overall, LINQPad is a powerful and versatile tool that can help developers work more efficiently and effectively with LINQ queries. Whether you are a seasoned developer or starting with LINQ, LINQPad is a tool worth exploring!
Here are a few examples of LINQ queries that you can try out in LINQPad:

Before we go to our examples, let us define our people and city classes first.

```c#
public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
    public string City { get; set; }
}
```

```c#
public class City
{
    public string Name { get; set; }
    public int Population { get; set; }
}
```

##Finding the average age of a group of people:

```c#
List<Person> people = new List<Person>
{
    new Person { Name = "Alice", Age = 25 },
    new Person { Name = "Bob", Age = 30 },
    new Person { Name = "Charlie", Age = 35 },
    new Person { Name = "David", Age = 40 }
};

var averageAge = people.Average(p => p.Age);

Console.WriteLine("Average age: " + averageAge);
```

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/wyystcp5fctvmh2woez6.png)

##Sorting a list of strings alphabetically:

```c#
List<string> names = new List<string> { "Alice", "Bob", "Charlie", "David" };

var sortedNames = names.OrderBy(n => n);

foreach (var name in sortedNames)
{
    Console.WriteLine(name);
}
```

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/0vn6wgr804575m2yz95c.png)

##Filtering a list of numbers to only include even numbers:

```c#
List<int> numbers = new List<int> { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

var evenNumbers = numbers.Where(n => n % 2 == 0);

foreach (var number in evenNumbers)
{
    Console.WriteLine(number);
}
```

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/lx4zbz30qtql5k08lqqm.png)

##Joining two lists of objects based on a common property:

```c#
List<Person> people = new List<Person>
{
    new Person { Name = "Alice", Age = 25, City = "New York" },
    new Person { Name = "Bob", Age = 30, City = "Chicago" },
    new Person { Name = "Charlie", Age = 35, City = "Los Angeles" },
    new Person { Name = "David", Age = 40, City = "Miami" }
};

List<City> cities = new List<City>
{
    new City { Name = "New York", Population = 8_500_000 },
    new City { Name = "Chicago", Population = 2_700_000 },
    new City { Name = "Los Angeles", Population = 4_000_000 },
    new City { Name = "Miami", Population = 470_000 }
};

var joinedData = from person in people
                 join city in cities on person.City equals city.Name
                 select new { Name = person.Name, City = person.City, Population = city.Population };

foreach (var data in joinedData)
{
    Console.WriteLine($"{data.Name} lives in {data.City}, which has a population of {data.Population}.");
}
```

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/6rtjttm9jt7bpu9c1ywd.png)

You can download LINQPad from the link below:
https://www.linqpad.net/