怎么控制网页的这个功能呢?
<tr> <td><b>验证码</b></td> <td><input id="register" style="width:88px; float:left" name="register" type="text" class="input1" value="点击显示验证码" onkeyup="javascript:if(this.value.length==6)checkrandimgfast(7);" onclick="this.value=''"/> <div id="m7" style="display:none; width:16px; float:left; margin-left:2px; padding-top:2px;"> <img id="rightError" src=""/></div></td> </tr>