Check inside method whether some optional argument was passed

Question

How do I check if an optional argument was passed to a method?

public void ExampleMethod(int required, string optionalstr = \"default string\",
    int optio         


        

Answer 1

You can't, so you need to find a different way to check for the "optional" parameter. You can pass in a null if the parameter isn't being used, and then check

if (optionalstr != null)
{
    // do something
}

You can also overload the method, having one taking the optional parameters and one that doesn't take the optional parameters. Also, you can make it so that the method without the optional parameters passes in nulls to one of the overloaded methods.

public void ExampleMethod(int required)
{
    ExampleMethod(required, null, 0);
}

public void ExampleMethod(int required, string optionalstr = "default string",
int optionalint = 10)
{

}