Occurs when the Value property has been changed in some way.
For the ValueChanged event to occur, the Value property can be changed in code, by clicking the up or down button, or by the user entering a new value that is read by the control. The new value is read when the user hits the ENTER key or navigates away from the control. If the user enters a new value and then clicks the up or down button, the ValueChanged event will occur twice.
NumericUpDown Class | Resco.Controls.NumericUpDown Namespace