JS dynamically adds list box item effect code_form effects

<table width="200" border="0" cellspacing="0"> <tr> <td colspan="3"><span id="selectmsg">*请选择1-3个知识点.</span></td> </tr> <tr> <td><select name="selectleft" size="10" id="selectleft"> <option value="1">1213123123</option> <option value="2">2123123123</option> <option value="3">3213123213</option> <option value="4">4123213213</option> <option value="5">5213123213</option> <option value="6">6213123213</option> </select></td> <td> <input type="button" id="addto" class="operateBtn" value=">>"> <input type="button" id="moveback" class="operateBtn" value="<<"> </td> <td><select name="selectright" size="10" id="selectright"> </select></td> </tr> </table>
[Ctrl A select all Note: If you need to introduce external Js, you need to refresh to execute

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