# Typed Value Validation (PostValidation)

This topic throws light on PostValidation, a feature that allows you to validate the typed value entered by the user.

## Content



[PostValidation](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.PostValidation.html) allows you to validate the typed [Value](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.Value.html) entered by the user.

The [PostValidation](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.PostValidation.html) class allows you to:

*   Check that the value matches one of the values in a pre-defined value list specified in the [Values](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.PostValidation.Values.html) property.
*   Test the value to see if it is below a minimum or above a maximum, that is you can test to see if the value belongs to an interval.
    
    You can even specify multiple intervals of allowed values. The intervals are defined in the [Intervals](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.PostValidation.Intervals.html) property where you specify minimum and maximum values for each interval, and also whether minimum and maximum values are used or ignored, and whether or not the inequality is strict (minimum/maximum value included).
    
*   Exclude some values using the [ValuesExcluded](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.PostValidation.ValuesExcluded.html) property.
*   Perform validation programmatically in the [PostValidating](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.PostValidating.html) event.

To distinguish between declarative and programmatic validation, use the PostValidation property with two possible values: [ValuesAndIntervals](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.PostValidation.ValidateValuesAndIntervals.html) and PostValidatingEvent. Note that PostValidatingEvent disables automatic validation of values and intervals. Call the ValidateValuesAndIntervals method from the event code if you want to combine event code with values and intervals validation.

## See Also

[Editing Date and Time Values](/componentone/docs/win/online-input/usingthec1inputcontr/editingdateandtimeva)