The answer given is excellent unless you require decimal places as others have pointed out.
In this event you need to extend the validation, add the using and vars below to get a culture variable value for the decimal separator if (!
Having adopted the Yoga way of life, Bipin also teaches Kriya Yoga to interested individuals. Notice how the Column Index and Row Index properties of Data Grid View Cell Validating Event Args parameter are used.At run time, if the validation fails, the Data Grid View displays a red exclamation icon in that cell (see below).Hovering the mouse pointer on the icon displays the Error Text that you set earlier.The Data Grid View control of Windows Forms is a versatile control that can help you create professional-looking data entry forms.
Index Of(dec Seperator) I like the extended validation.