Friends say it's not compatible. Last night I went back and debugged a compatible version: Copy code The code is as follows: <br>function selectIt(action){ <br> var testform=document.getElementById("bdkey"); <br> for(var i=0 ;i<testform.elements.length;i ){ <BR> if(testform .elements[i].type=="checkbox"){ <BR> e=testform.elements[i]; <BR> e.checked=(action=="selectAll")?1:(!e.checked) ; <BR> bdkey"> <br><p class="STYLE1"> <br>Select all<br><input type="checkbox" name="selectAll" value="checkbox" onClick="selectIt('selectAll ')"><br> <br>Invert selection<br><input type="checkbox" name="invest" value="checkbox" onClick="selectIt()"><br> <br>Item1 <br><input type="checkbox" name="checkbox" value="checkbox"> <br><br> <br>Item2 <br><input type="checkbox" name=" checkbox" value="checkbox"><br> <br>Item3 <br><input type="checkbox" name="checkbox" value="checkbox"><br> <br>Item4 <br><input type="checkbox" name="checkbox" value="checkbox"><br> <br>Item5 <br><input type="checkbox" name="checkbox" value="checkbox" > <br></p> <br></form> <br></body><br><br><br><br><br> <br> <br> </div> <br> <div class="htmlarea"> <textarea id="runcode79668"> Select all <meta http-equiv="Content-Type" content="text/html; charset=gbk"> Reverse election Item1 Item2 <form name="bdkey" id="bdkey"> Item3 <p class="STYLE1"> Item4 <input type="checkbox" name="selectAll" value="checkbox" onclick="selectIt('selectAll')"> Item5 <input type="checkbox" name="invest" value="checkbox" onclick="selectIt()"> <input type="checkbox" name="checkbox" value="checkbox"> <input type="checkbox" name="checkbox" value="checkbox"> <input type="checkbox" name="checkbox" value="checkbox"> <input type="checkbox" name="checkbox" value="checkbox"><input type="checkbox" name="checkbox" value="checkbox"></p> </form> [Ctrl A Select all Note: </textarea>If you need to introduce external Js, you need to refresh to execute <br>]<input onclick="runEx('runcode79668')" type="button" value="杩愯"> </div>