Validating windows vista
If you cancel the Validating event, the behavior of the control will be determined by what value that you assigned to Auto Validate.If you assigned Enable Prevent Focus Change, canceling the event will cause the Validated event not to occur.For example, if you have code in a Validated event that attempts to cancel the data binding, the data binding will still occur.In this case, to perform validation in the Validated event, change the control's Data Source Update Mode property (under (Databindings)\(Advanced)) from On Validation to Never, and add So when does a control's data get validated? You can use either implicit or explicit validation, depending on the needs of your application.A is a string made up of characters from a masking language that specifies which characters can be entered at any given position in the text box. If the user types an incorrect entry, for example, the user types a letter when a digit is required, the control will automatically reject the input.The masking language that is used by Masked Text Box is very flexible.
The control also works well when bound to a data source.The Format event on a data binding can be used to reformat incoming data to comply with the mask, and the Parse event can be used to reformat outgoing data to comply with the specifications of the data field. If you want full programmatic control over validation, or need to perform complex validation checks, you should use the validation events built into most Windows Forms controls.