asp.net加法计算 如果使用js 请给出详细代码
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<table style="text-align:center; width:300px;"> <tr> <td> <input id="tb_numberA" type="text" value="0"/> </td> <td class="auto-style2">+</td> <td class="auto-style2"> <input id="tb_numberB" type="text" value="0"/> </td> <td class="auto-style2"> <input id="Button1" type="button" value="=" onkeyup="sum()"/> </td> <td class="auto-style2"> <input id="result" type="text" /> </td> </tr> </table>