Multiple ways to select all in checkbox, constantly updated [Original]_Form special effects

Copy code The code is as follows:

<form id="form1" name="form1" method="post" action=""> <input type="checkbox" name="sid" value="1"> <input type="checkbox" name="sid" value="2"> <input type="checkbox" name="sid" value="3"> <input type="checkbox" name="sid" value="4"> <input name="thes" type="button" onclick="javascript:selectall1()" value="第一种"> <input name="thes" type="button" onclick="javascript:selectall2()" value="第二种"> <input name="thes" type="button" onclick="javascript:selectall3()" value="第三种"> <input name="thes" type="button" onclick="javascript:selectall4('sid')" value="第四种"> <input name="thes" type="button" onclick="javascript:selectall5('form1','sid')" value="第五种"> </form>
[Ctrl A Select all Note: If you need to introduce external Js, you need to refresh to execute

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PS: The above three methods , can achieve the effect, but if you want to achieve (select all|inverse selection), you need to add as required