金额验证

<tr>
<td>
                        合同金额<em>*</em>
                    </td>
                    <td>
                        <asp:TextBox ID="txt_HeTongMoney" runat="server" Style="padding: 0 2px;  112px;"
                            onKeyUp="if(isNaN(value))execCommand('undo')" onafterpaste="if(isNaN(value))execCommand('undo')"
                            onblur="if(isNaN(value))execCommand('undo')" MaxLength="11" ToolTip="装饰合同中同甲方签订的最终金额"></asp:TextBox>&nbsp;元
                    </td>
</tr>