C# winform listView CheckBoxes 全选,反选怎么做

C# code

private void checkBox3_CheckedChanged(object sender, EventArgs e)        {            if (checkBox3.Checked)            {                listView4.Focus();                foreach (ListViewItem item in listView4.Items)                {                    item.Selected = true;                }            }        }

这样不能全选。。请各位帮忙解释下。。。该怎么做全选跟反选。。谢谢贴出代码

[解决办法]
item.Checked = true; //全选
item.Checked = !item.Checked; // 反选