Thank you for contacting Telerik support.
You should set the TextMaskFormat
property to ExcludePromtAndLiterals
. This property determines whether literals (like minus symbol) and prompt characters are included in the value property:
I would kindly ask you to open a new support ticket and send me a sample project which demonstrates the issue with RadGridView and Mask Column. This will allow us to investigate your case and provide you with adequate support.
Thank you for your cooperation.
the Telerik team