MahApps/MahApps.Metro — pull request #899 by xxMUROxx (2013-12-28 11:01:00+00:00)
Title: Feature/numeric up down

The user should not be able to enter invalid characters to the NumericUpDown control.
An invalid character is defined as character other than:
* Positive/Negative sign (only if it is the first character)
* Number
* Decimal Seperator (only if there is none present)

Furthermore the Paste action is monitored.

Referenced issues: #890