extension methods allow existing compiled types (specifically, classes, structures, or interface implementations) as well as types currently being compiled (such as types in a project that contains extension methods) to gain new functionality without needing to directly update the type being extended.
+extension method must be declared with the static keyword
+all extension methods are marked as such by using the this keyword
+every extension method can be called either from the correct instance in memory or statically via the defining static class!
Example
+extension method must be declared with the static keyword
+all extension methods are marked as such by using the this keyword
+every extension method can be called either from the correct instance in memory or statically via the defining static class!
*if you do not explicitly import the correct namespace, the extension methods are not available for that C# code file
Example
Declare a class
public class Car
{
public int Speed;
public int SpeedUp()
{
return ++Speed;
}
}
another class, trying to call a member of the Car class
public static class CarExtensions
{
public static int SlowDown(this Car c)
{
// Error! This method is not deriving from Car!
return --Speed;
}
}
To success,
public static class CarExtensions
{
public static int SlowDown(this Car c)
{
// OK!
return --c.Speed;
}
}
