Are there any performance implications in CanExecuteCommand?

Question

What are the implications of using the CanExecuteCommand ICommand object. Does this method repeat over and over?

I need to iterate through a collection of approximately 200 objects, based on which she decided whether the button bound to the command should be enabled? CanExecuteCommand runs again, which slows down my application.

Answer 1

The interface is ICommandas follows:

public interface ICommand
{
    // two methods
    bool CanExecute(object parameter);
    void Execute(object parameter);

    // one event
    event EventHandler CanExecuteChanged;
}

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Josh Smith RelayCommand CommandManager WPF CanExecuteChanged:

public event EventHandler CanExecuteChanged
{
    add { CommandManager.RequerySuggested += value; }
    remove { CommandManager.RequerySuggested -= value; }
}

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@Will , . RelayCommand, , 80% . , RelayCommand Prism DelegateCommand CanExecuteChanged .

Answer 2

: . -, OnPropertyChanged ViewModelBase, CanExecuteChanged Command , , One Way . PerrypheralFrameowrk.WPF, nuget codeplex. . Codeplex wiki , .