Kotlin "apply" equivalent in C#

Question

When using Kotlin, one could use apply to set multiple properties of an existing object and keeping the code cleaner, for example instead of:

person.firstName = "John"
person.lastName = "Doe"
person.phone = "123 456 789"

We can use:

person.apply {
   firstName = "John"
   lastName = "Doe"
   phone = "123 456 789"
}

Is there an equivalent to the apply in C#?

The closest to this is the using but it can't be used this way as far as I know.

Edit: I know of object initializer in C#, but I'm actually looking for something that can be done for existing objects (for example an object fetched from the database).

Answer 1

Try this.... https://dev.to/amay077/kotlins-scope-functions-in-c-pbn

Code pasted below for convenience, but the above link is the source...

static class ObjectExtensions 
{
  // Kotlin: fun <T, R> T.let(block: (T) -> R): R
  public static R Let<T, R>(this T self, Func<T, R> block) 
  {
    return block(self);
  }

  // Kotlin: fun <T> T.also(block: (T) -> Unit): T
  public static T Also<T>(this T self, Action<T> block)
  {
    block(self);
    return self;
  }   
}

Can be used like this....

var model = new MyModel().Also(m => {
  m.Initialize();
  m.Load(path);
});

Answer 2

You can use it in this way with object initializers:

var person = new Person
{
   FirstName = "John",
   LastName = "Doe",
   Phone = "123 456 789"
};

Or with a constructor:

var person = new Person("John", "Doe", "123 456 789");

Your class would have to look like this for the constructor option:

class Person
{
    public Person(string firstName, string lastName, string phone)
    {
        FirstName = firstName;
        LastName = lastName;
        Phone = phone;
    }

    public string FirstName { get;set; }
    public string LastName { get;set; }
    public string Phone { get;set; }
}