Javascript知识【案例：注册表单校验】

  <div id="divbg">
     <div id="divFormId">
        <form action="#" method="get" onsubmit="return checkFormData()">
           <table  width="550">
              <tr>
                 <td colspan="3">
                    <font color="#3164af" size="5">会员注册</font> USER REGISTER
                 </td>
              </tr>
              <tr>
                 <td align="right">用户名</td>
                 <td colspan="2"><input type="text" id="username" name="username" size="50"/><span id="usernameSpan" class="errorMsg"></span></td>
              </tr>
              <tr>
                 <td align="right">密码</td>
                 <td colspan="2"><input type="password" id="pwd" name="pwd" size="50"/><span id="pwdSpan" class="errorMsg"></span></td>
              </tr>
              <tr>
                 <td align="right">确认密码</td>
                 <td colspan="2"><input type="password" id="repwd" name="repwd" size="50"/><span id="repwdSpan" class="errorMsg"></span></td>
              </tr>
              <tr>
                 <td align="right">Email</td>
                 <td colspan="2"><input type="text" id="email" name="email" size="50"/> </td>
              </tr>
              <tr>
                 <td align="right">姓名</td>
                 <td colspan="2"><input name="text" id="name" name="name" size="50"/> </td>
              </tr>
              <tr>
                 <td align="right">性别</td>
                 <td colspan="2">
                    <input type="radio" name="sex" value="man" checked="checked" />男
                    <input type="radio" name="sex" value="woman" />女
                 </td>
              </tr>
              <tr>
                 <td align="right">出生日期</td>
                 <td colspan="2"><input type="text" id="birthday" name="birthday" size="50"/> </td>
              </tr>
              <tr>
                 <td width="80" align="right">验证码</td>
                 <td width="100"><input type="text" id="verifyCode" name="verifyCode" /> </td>
                 <td><img src="img/verifyCode.jpg" /> </td>
              </tr>
              <tr>
                 <td></td>
                 <td colspan="2">
                    <input type="image" src="img/submit.jpg"  />
                 </td>
              </tr>
           </table>

        </form>
     </div>
  </div>