Question

Now I custom a control like slider, and I want to custom a ValueChanged event handle like the slider’s ValueChanged event handle.

the event as follow:

public delegate void ValueChangedEventHandle(object sender, RangeBaseValueChangedEventArgs e);
public event ValueChangedEventHandle ValueChanged;

When the value changed, I call the event ValueChanged, like this

    private void Changed(double value)
    {
      `enter code here`if (ValueChanged != null)
      {
           rangeBaseValueChangedEventArgs.NewValue = newValue;
           rangeBaseValueChangedEventArgs.OldValue = oldValue;
           ValueChanged(this, RangeBaseValueChangedEventArgs);
      }
}

But the class RangeBaseValueChangedEventArgs is a sealed class and have no constructor, so I cann’t create a new instance.

Anyone know how to do it, I just want to define an event argument like the slider’s RangeBaseValueChangedEventArgs , so I can use it like the slider.

Thank you in advance for.

-Alen

Answer 1

Just create your own EventArgs class inheriting from RoutedEventArgs and make it have the same properties.