Determine Age and validate minimum age from date selected in ASP.Net AJAX CalendarExtender control

Hi Mohdimran11189,

Please try the following way...

<div>
        <uc:ToolkitScriptManager runat="server"></uc:ToolkitScriptManager>   
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
        <asp:Image runat="server" Id="img1"/>
        <uc:CalendarExtender runat="server" PopupButtonID="img1" TargetControlID="TextBox1"></uc:CalendarExtender>
        <asp:RangeValidator ErrorMessage="Invalid Date" ControlToValidate="TextBox1" runat="server"
        Type="Date" MinimumValue="1971-01-01" MaximumValue="1998-12-31"/>
    </div>

Thanks and Regards,

Rk_Hirpara

Refer: 1. Validate Age when Birth Date is selected in ASP.Net AJAX CalendarExtender Control