# IValidation Namespace: **Wisej.Web** Assembly: **Wisej.Framework** (4.0.0.0) Provides access to the validation events and properties property for controls that support validation. {% tabs %} {% tab title="C#" %} ```csharp public interface IValidation ``` {% endtab %} {% tab title="VB.NET" %} ```visual-basic Public Interface IValidation ``` {% endtab %} {% endtabs %} Using [IValidation](/api/wisej.web/interfaces/wisej.web.ivalidation.md) allows developers to use uniform code to access the validation-related properties and events used by the control. ```csharp // Old code if (control is TextBox) ((TextBox)control).InvalidMessage = "Required"; else if (control is ComboBox) ((ComboBox)control).InvalidMessage = "Required"; // etc... // New code if (control is IValidation) ((IValidation)control).InvalidMessage = "Required"; ``` ## Properties ### ![](/files/hsR4ok3152WyAf8J2C1u) InvalidMessage [String](https://docs.microsoft.com/dotnet/api/system.string): Returns or sets the invalid message that is shown in the invalid tooltip. ## Events ### ![](/files/hsR4ok3152WyAf8J2C1u) Validated [EventHandler](https://docs.microsoft.com/dotnet/api/system.eventhandler) Fired when the control is finished validating. ### ![](/files/hsR4ok3152WyAf8J2C1u) Validating [CancelEventHandler](https://docs.microsoft.com/dotnet/api/system.componentmodel.canceleventhandler) Fired when the control is validating. ## Implemented By | Name | Description | | --------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [CheckBox](/api/wisej.web/buttons/wisej.web.checkbox.md) | Represents a check box control. | | [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md) | Displays a [ListBox](/api/wisej.web/lists-and-grids/listbox.md) in which a check box is displayed to the left of each item. | | [ComboBox](/api/wisej.web/lists-and-grids/combobox.md) | Represents a combo box control. | | [DateTimePicker](/api/wisej.web/editors/wisej.web.datetimepicker.md) | Represents a control that allows the user to select or type a date and a time. | | [DomainUpDown](/api/wisej.web/editors/domainupdown.md) | Represents a spinner control that displays string values. | | [ListBox](/api/wisej.web/lists-and-grids/listbox.md) | Represents a control to display a list of items. | | [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md) | Provides a common implementation of members for the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) and [ComboBox](/api/wisej.web/lists-and-grids/combobox.md) classes. | | [MaskedTextBox](/api/wisej.web/editors/maskedtextbox.md) | Uses a mask to distinguish between proper and improper user input. | | [NumericUpDown](/api/wisej.web/editors/wisej.web.numericupdown.md) | Represents a spinner control that displays numeric values. | | [RadioButton](/api/wisej.web/buttons/wisej.web.radiobutton.md) | Enables the user to select a single option from a group of choices when paired with other [RadioButton](/api/wisej.web/buttons/wisej.web.radiobutton.md) controls. | | [TextBox](/api/wisej.web/editors/wisej.web.textbox.md) | Represents a text box control that allows the user to enter any value. | | [TextBoxBase](/api/wisej.web/editors/wisej.web.textboxbase.md) | Implements the basic functionality required by text controls. | | [UpDownBase](/api/wisej.web/editors/wisej.web.updownbase.md) | Implements the basic functionality required by a spin box (also known as an up-down control). | | [DataGridViewComboBoxEditingControl](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewcomboboxeditingcontrol.md) | Represents a [ComboBox](/api/wisej.web/lists-and-grids/combobox.md) control that can be hosted in a [DataGridViewComboBoxCell](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewcomboboxcell.md). | | [DataGridViewDateTimePickerEditingControl](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewdatetimepickereditingcontrol.md) | Represents a [DateTimePicker](/api/wisej.web/editors/wisej.web.datetimepicker.md) control that can be hosted in a [DataGridViewDateTimePickerCell](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewdatetimepickercell.md). | | [DataGridViewMaskedTextBoxEditingControl](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewmaskedtextboxeditingcontrol.md) | Represents a [MaskedTextBox](/api/wisej.web/editors/maskedtextbox.md) control that can be hosted in a [DataGridViewMaskedTextBoxCell](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewmaskedtextboxcell.md) cell. | | [DataGridViewNumericUpDownEditingControl](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewnumericupdowneditingcontrol.md) | Represents a [NumericUpDown](/api/wisej.web/editors/wisej.web.numericupdown.md) control that can be hosted in a [DataGridViewNumericUpDownCell](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewnumericupdowncell.md). | | [DataGridViewTextBoxEditingControl](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewtextboxeditingcontrol.md) | Represents a [TextBox](/api/wisej.web/editors/wisej.web.textbox.md) control that can be hosted in a [DataGridViewTextBoxCell](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewtextboxcell.md) cell when the cell's [WrapMode](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewcellstyle.md#wrapmode) is set to [False](/api/wisej.web/lists-and-grids/datagridview/wisej.web.datagridviewtristate.md#fields). | | [ListViewComboBox](/api/wisej.web/lists-and-grids/wisej.web.listviewcombobox.md) | The TreeViewComboBox control represents a [UserComboBox](/api/wisej.web/lists-and-grids/wisej.web.usercombobox.md) control with a [ListView](/api/wisej.web/lists-and-grids/listview.md) as the drop down panel. | | [TagTextBox](/api/wisej.web/editors/tagtextbox.md) | Represents a data field that displays a list of selectable and removable tags. The control recognizes tags as the user types and adds in front of the editable field. | | [TimeUpDown](/api/wisej.web/editors/timeupdown.md) | Represents a spinner control that displays [TimeSpan](https://docs.microsoft.com/dotnet/api/system.timespan) values. | | [TreeViewComboBox](/api/wisej.web/lists-and-grids/wisej.web.treeviewcombobox.md) | The TreeViewComboBox control represents a [UserComboBox](/api/wisej.web/lists-and-grids/wisej.web.usercombobox.md) control with a [TreeView](/api/wisej.web/lists-and-grids/treeview.md) as the drop down panel. | | [TypedTextBox](/api/wisej.web/editors/wisej.web.typedtextbox.md) | Represents a text box control that allows the user to enter a typed value. | | [Upload](/api/wisej.web/content/upload.md) | Represent an upload widget. Allows users to selected one or more files and upload them to the server. | | [UserComboBox](/api/wisej.web/lists-and-grids/wisej.web.usercombobox.md) | The UserComboBox control represents a [ComboBox](/api/wisej.web/lists-and-grids/combobox.md) control with a custom panel that drops down when the user clicks the down arrow. | --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.ivalidation.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. 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