Linq select new

The Select method in LINQ!

Select is a LINQ method that allows you to project an existing collection of objects into a new collection of objects. It's a powerful way to transform and shape your data.

Here's the basic syntax:

var result = source.Select(x => new { /* properties */ });

In this example:

• source is the original collection of objects.
• x is an element from the source collection.
• new { /* properties */ } is the new object that will be created for each element in the source collection.

The Select method takes a lambda expression as an argument, which defines the transformation from the original object to the new object. The lambda expression is executed for each element in the source collection, and the resulting objects are collected in a new collection.

Here are some examples:

Example 1: Selecting a subset of properties

var customers = new[] { new { Id = 1, Name = "John", Email = "[email protected]" },
                        new { Id = 2, Name = "Jane", Email = "[email protected]" } };

var result = customers.Select(c => new { c.Name, c.Email });

In this example, we select only the Name and Email properties from each customer object and create a new collection of anonymous objects with these properties.

Example 2: Selecting a new object with calculated properties

var orders = new[] { new { Id = 1, CustomerId = 1, Total = 100 },
                     new { Id = 2, CustomerId = 1, Total = 200 },
                     new { Id = 3, CustomerId = 2, Total = 50 } };

var result = orders.Select(o => new { CustomerName = "Customer " + o.CustomerId, Total = o.Total });

In this example, we select a new object with two properties: CustomerName and Total. The CustomerName property is calculated by concatenating a string with the CustomerId property, and the Total property is taken from the original orders collection.

Example 3: Selecting a new object with a different type

var customers = new[] { new { Id = 1, Name = "John", Email = "[email protected]" },
                        new { Id = 2, Name = "Jane", Email = "[email protected]" } };

var result = customers.Select(c => new CustomerSummary { Name = c.Name, Email = c.Email });

In this example, we select a new object of type CustomerSummary, which has two properties: Name and Email. The CustomerSummary class is defined elsewhere in your code.

These are just a few examples of what you can do with the Select method in LINQ. It's a powerful tool that allows you to transform and shape your data in many creative ways!