Question

I am converting some java code C# for use in my MonoDroid application. I have some snippets where interfaces are declared and then initialized in to objects. I am not 100% sure on the best approach to implement these in to C#.

For example:

public class NumberPicker {

    public interface Formatter {
        String toString(int value);
    }

    public static final NumberPicker.Formatter TWO_DIGIT_FORMATTER =
            new NumberPicker.Formatter() {
             //some code here
            };

}

What would be the equivalent or best approach to do this in c#?

Answer 1

for simple “single-use” interfaces with one function (like event listeners, for example), you could think of rewriting the code to use delegates and anonymous functions instead.

delegate String Formatter(int n);
...

Formatter TWO_DIGIT_FORMATTER = delegate(int n) {
                                         //code here
                                       };

you can then use TWO_DIGIT_FORMATTER like a function ( TWO_DIGIT_FORMATTER(12) ).

Anonymous classes (which is what’s happening in your java code) don’t exist in C#, but delegates suffice in cases like this.