Command Pattern : How to pass parameters to a command?

Question

My question is related to the command pattern, where we have the following abstraction (C# code) :

public interface ICommand
{
    void Execute();
}
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Answer 1

Based on the pattern in C#/WPF the ICommand Interface (System.Windows.Input.ICommand) is defined to take an object as a parameter on the Execute, as well as the CanExecute method.

interface ICommand
            {
                bool CanExecute(object parameter);
                void Execute(object parameter);
            }

This allows you to define your command as a static public field which is an instance of your custom command object that implements ICommand.

public static ICommand DeleteCommand = new DeleteCommandInstance();

In this way the relevant object, in your case a person, is passed in when execute is called. The Execute method can then cast the object and call the Delete() method.

public void Execute(object parameter)
            {
                person target = (person)parameter;
                target.Delete();
            }