How to add ASP Validators to Classic controls?

ASP Validator controls work well with Syncfusion’s ASP.NET Classic TextBox controls like NumericTextBox, CurrencyTextBox, DateTimeTextBox, etc.

In a web page, add the required Classic control, like, DateTimeTextBox control. Drag and drop the validation controls from ASP Tool box. In ControlToValidate, specify the ID of the Classic control added in the web page.

Used here is DateTimeTextBox with RequiredField validator, that ensures whether the corresponding control has some value before proceeding to form submission. On Form submission, an error message is displayed when the control is not populated.

You can modify the validator condition and error message as per your requirement. Refer the following code example that uses the RequiredField validator.

ASPX

<syncfusion:DateTimeTextBox ID="datetime" runat="server" Format="Short" EnableNullDate="True" IsNullDate="True" NullString=" " />
<asp:RequiredFieldValidator runat="server" ID="ReqFieldValid" ErrorMessage="Required" ControlToValidate="datetime"></asp:RequiredFieldValidator>
    <asp:Button Text="Validate" ID="okbtn" runat="server" UseSubmitBehavior="true" OnClick="okbtn_Click" />

The output for DateTimeTextBox with validator on form submission is displayed as follows.

Figure 1: DateTimeTextBox with RequiredField validator