Textbox with date validations ASP.NET C#

  <div>

            <span class="h4">4. (b)</span> <span class="text-danger h3">*</span>

            

                    <b>Date of Issue of Medical Certificate (MM/DD/YYYY)</b></div>

                <div>

                    &nbsp&nbsp&nbsp<asp:TextBox runat="server" ID="txtDOIMC" ClientIDMode="Static" MaxLength="10" CssClass="form-control"

                        placeholder="eg. 02/30/1978"></asp:TextBox>

                    <asp:RequiredFieldValidator ID="RequiredFieldValidator7" runat="server" ControlToValidate="txtDOIMC"

                        CssClass="text-danger" Display="Dynamic" ErrorMessage="Can't leave blank." SetFocusOnError="True"

                        ValidationGroup="transfer_request"></asp:RequiredFieldValidator>

                    <asp:RegularExpressionValidator ID="regcheckdate" runat="server" ControlToValidate="txtDOIMC"

                        Display="Dynamic" ErrorMessage="Invalid Date Format" SetFocusOnError="True" ValidationGroup="transfer_request"

                        CssClass="text-danger" ValidationExpression="^(0[1-9]|1[0-2])\/(0[1-9]|1\d|2\d|3[01])\/(19|20)\d{2}$"></asp:RegularExpressionValidator>

                </div>

        </div>