Overview
This is how you extend a class that already exists and that you don’t have access to. More info can be found here.
Examples
First declare a static class, then create a static method that has this in front of the first parameter… Done!
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
public class Extensions {
public static void SayHello(this Person person) {
Console.WriteLine("Hello, my name is {0} and I'm {1}", person.Name, person.Age);
}
public static void SayThing(this Person person, string thing) {
Console.WriteLine("Hello {0} said {1}", thing, person.Name);
}
}
public class Program {
public static void Main(string[] args) {
var person = new Person { Name="Tom", Age=5 };
person.SayHello(); // Hello, my name is Tom and I'm 5
person.SayThing("Random"); // Hello Random said Tom
}
}