First: Add all you checkboxes to a List<CheckBox>
.
Then your property could be sth. like
public bool itemchecked
{
get
{
var checkedBoxes = new List<CheckBox>();
foreach(var item in AllCheckBoxes)
{
if(item.Checked)
{
checkedBoxes.Add(item);
}
}
return checkedBoxes;
}
}
You could also use a linQ-Expression to return the list.