# Displaying NULL and Empty Values

This topic covers information about displaying NULL and Empty Values.

## Content



When a control is not in edit mode or is read-only, null values are displayed according to the [NullText](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.NullText.html) property (which can be overridden in [DisplayFormat](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.DisplayFormat.html)). If the property [EmptyAsNull](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.EmptyAsNull.html) is set to **True** (default: **False**), empty strings are also displayed with the same NullText string. The EmptyAsNull property can also be overridden in EmptyAsNull. In edit mode, the NullText and EmptyAsNull properties of the [EditFormat](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.EditFormat.html) object take effect, instead of those of DisplayFormat.

In edit mode with an active [EditMask](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.EditMask.html), the null value and the empty string are shown as an empty mask with literals in their places and prompt characters filling the rest.

When editing a date-time value with the [DateTimeInput](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.DateTimeInput.html) property set to **True**, the null value is represented by an empty control. When the user starts editing with a keystroke or mouse click, the control immediately turns to a non-null value, namely, to the last non-null value assigned to the control or to today’s date.

In programmatic formatting ([FormatType](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.FormatType.html) set to [UseEvent](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.FormatTypeEnum.html)), the [Formatting](/componentone/api/win/online-input/dotnet-framework-api/C1.Win.C1Input.4.8/C1.Win.C1Input.C1TextBox.Formatting.html) event is only called for non-null values.

## See Also

[Entering NULL and Empty Values](/componentone/docs/win/online-input/usingthec1inputcontr/handlingnullandempty/enteringnullandempty)