function treeChecked(selected, treeMenu) {
var roots = $('#' + treeMenu).tree('getRoots');
if (selected.checked) {
for ( var i = 0; i < roots.length; i++) {
var node = $('#' + treeMenu).tree('find', roots[i].id);
$('#' + treeMenu).tree('check', node.target);
}
} else {
for ( var i = 0; i < roots.length; i++) {
var node = $('#' + treeMenu).tree('find', roots[i].id);
$('#' + treeMenu).tree('uncheck', node.target);
}
}
}
<input title="全选/反选" type="checkbox" onClick="treeChecked(this,'treeMenu')"/>