How to add functions in a native C # class, in my case, I tried to do in System.Math just as test:
public class Math
{
public static double test(double a)
{
return a;
}
}
And call it like this:
Math.test(10);
But I did not get the expected result. How could I add the method in this class?
This is not possible today, and there is little advantage to doing this. Create a new and good class.
public class MathExt {
public static double test(double a) => a;
}
MathExt.test(10);
In addition,
I believe that what you are looking for is called Extension Methods .
See more at: extension !
Using this concept, you can create extensions for all classes and structures, as long as they are not static.
The Math class is static and can not be extended:
Theotheranswersevenseemtowork,butinfactyouwouldbeaccessinganewclassandnottheexistingone:System.Math.
Seethedifferencebelow:
Listofmethodsofthenewclass,comparedtothelistofmethodsofclassSystem.Mathbelow:
Here'sanexampleofwhatadoubleextensionmightlookliketogetanidea:
classProgram{publicstaticvoidMain(){doubledez=10;Console.WriteLine("Dobro(10) => {0}", dez.Dobro());
Console.WriteLine("Metade(10) => {0}", dez.Metade());
}
}
public static class DoubleEx
{
public static double Dobro(this double a)
{
return a * 2;
}
public static double Metade(this double a)
{
return a / 2;
}
}
With the following output: Double (10) = > 20 Half (10) = > 5