WPF TextBox Trigger Text changed Event

Question

 hi

In reference to the following thread:

http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/fd819518-605a-46ae-a9e4-26556d0f3e15

I have a issue with the Galasoft dll(I cant use it due to IPR issues)

Is there any other work around to achieve the same without MvvmLightToolKit

Any help will be appreciated.

Answer 1

Do you mean to have access to it in your viewmodel?

Answer 2

If you are referring to the "Relay Command", it's not Galasoft's IP anyway, they've just made a very nice implementation.

Before I started using MVVMLite I had my own library of such things, as you will find it scattered all over the Internet.

One of the most well known versions/sources for the code of a Relay Command is MSDN Magazine.

    

public class RelayCommand : ICommand
{
    #region Fields

    readonly Action<object> _execute;
    readonly Predicate<object> _canExecute;        

    #endregion // Fields

    #region Constructors

    public RelayCommand(Action<object> execute)
    : this(execute, null)
    {
    }

    public RelayCommand(Action<object> execute, Predicate<object> canExecute)
    {
        if (execute == null)
            throw new ArgumentNullException("execute");

        _execute = execute;
        _canExecute = canExecute;           
    }
    #endregion // Constructors

    #region ICommand Members

    [DebuggerStepThrough]
    public bool CanExecute(object parameter)
    {
        return _canExecute == null ? true : _canExecute(parameter);
    }

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

    public void Execute(object parameter)
    {
        _execute(parameter);
    }

    #endregion // ICommand Members
}

     

Regards,
Pete

---

#PEJL

Answer 3

Hi Parsita,

I think you could refer to AttachedCommandBehavior, there is an AttachedCommandBehavior(ACB) library,

http://marlongrech.wordpress.com/2008/12/13/attachedcommandbehavior-v2-aka-acb/

This feature will help you hook command to any event, and it has provided a complete sample you could refer to.

Best regards,

---

Sheldon _Xiao[MSFT]
MSDN Community Support | Feedback to us
Microsoft
Please remember to mark the replies as answers if they help and unmark them if they provide no help.