| CalendarView for WinForms > Using Controls > DateEdit Features > Data Validation > Pre-validation |
Pre-validation is raw string validation, which means that rules are applied before parsing.
DateEdit allows controlling pre-validation of input string through the PreValidation property. The control provides various pre-validation options, as follows:
The following image shows the DateEdit control displaying validation error message.

The following code snippet shows how to set various properties to apply pre-validation in DateEdit.
' Apply PreValidation in DateEdit C1DateEdit1.PreValidation.CaseSensitive = True C1DateEdit1.PreValidation.ErrorMessage = "Input mismatch with pattern string" C1DateEdit1.PreValidation.ItemSeparator = "|" C1DateEdit1.PreValidation.PatternString = "00|11" C1DateEdit1.PreValidation.Validation = C1.Win.C1Input.PreValidationTypeEnum.ExactList
// apply PreValidation in DateEdit c1DateEdit1.PreValidation.CaseSensitive = true; c1DateEdit1.PreValidation.ErrorMessage = "Input mismatch with pattern string"; c1DateEdit1.PreValidation.ItemSeparator = "|"; c1DateEdit1.PreValidation.PatternString = "00|11"; c1DateEdit1.PreValidation.Validation = C1.Win.C1Input.PreValidationTypeEnum.ExactList;