HTML表单中单个按钮变成多选按钮问题

function selectAllDels() {

var allCheckBoxs = document.getElementsByName("GroupAll");

var desc = document.getElementById("allChecked");

var selectOrUnselect = false;

for (var i = 0; i < allCheckBoxs.length; i++) {

if (allCheckBoxs[i].checked) {

selectOrUnselect = true; break;

}

}

if (selectOrUnselect) {

_allUnchecked(allCheckBoxs);

} else {

_allchecked(allCheckBoxs);

}

}

function _allchecked(allCheckBoxs) {

for (var i = 0; i < allCheckBoxs.length; i++) {

allCheckBoxs[i].checked = true;

}

}

function _allUnchecked(allCheckBoxs) {

for (var i = 0; i < allCheckBoxs.length; i++) {

allCheckBoxs[i].checked = false;

}

}