체크박스(checkbox) 전체선택/해제/반전 > script

var chkFlag = false;
function chkAll() {
    var obj = document.getElementsByName("chk");
   chkFlag = !chkFlag
    for (var i=0; i<obj.length; i++) obj[i].checked = chkFlag;
}

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<script type="text/JavaScript">
function chkBox(bool) { // 전체선택/해제
    var obj = document.getElementsByName("chk[]");
    for (var i=0; i<obj.length; i++) obj[i].checked = bool;
}
function revBox() { // 전체반전
    var obj = document.getElementsByName("chk[]");
    for (var i=0; i<obj.length; i++) obj[i].checked = !obj[i].checked;
}
</script>

<table border=1>
<tr bgcolor=#efefef>
    <td><INPUT type=checkbox onclick=chkBox(this.checked)> 선택</td>
</tr>
<tr><td><INPUT type=checkbox name=chk[] value=100> 이효리</td></tr>
<tr><td><INPUT type=checkbox name=chk[] value=200> 성유리</td></tr>
<tr><td><INPUT type=checkbox name=chk[] value=300> 이진</td></tr>
<tr><td><INPUT type=checkbox name=chk[] value=400> 옥주현</td></tr>
</table>

<INPUT type=button value="전체반전" onclick=revBox()>