asp.net的Treeview怎么实现父节点选中子结点全部选中

1.这是js代码

<script type="text/javascript">
         function Davidovitz_HandleCheckbox() {

            var element = event.srcElement;

            if (element.tagName == "INPUT" && element.type == "checkbox") {

                var checkedState = element.checked;

                while (element.tagName != "TABLE") // Get wrapping table

                {

                    element = element.parentElement;

                }

 

                Davidovitz_UnCheckParents(element); // Uncheck all parents

 

                element = element.nextSibling;

 

                if (element == null) // If no childrens than exit

                    return;

 

                var childTables = element.getElementsByTagName("TABLE");

                for (var tableIndex = 0; tableIndex < childTables.length; tableIndex++) {

                    Davidovitz_CheckTable(childTables[tableIndex], checkedState);

                }

            }

        }

 

        // Uncheck the parents of the given table, Can remove the recurse (redundant)

        function Davidovitz_UnCheckParents(table) {

            if (table == null || table.rows[0].cells.length == 2) // This is the root

            {

                return;

            }

            var parentTable = table.parentElement.previousSibling;

            Davidovitz_CheckTable(parentTable, false);

            Davidovitz_UnCheckParents(parentTable);

        }

 

        // Handle the set of checkbox checked state

        function Davidovitz_CheckTable(table, checked) {

            var checkboxIndex = table.rows[0].cells.length - 1;

            var cell = table.rows[0].cells[checkboxIndex];

            var checkboxes = cell.getElementsByTagName("INPUT");

            if (checkboxes.length == 1) {

                checkboxes[0].checked = checked;

            }

        }

    </script>

2.在page_load事件里加这么一句话进行注册事件

TreeView1.Attributes.Add("onclick", "Davidovitz_HandleCheckbox()");

就可以完全实现父节点选中而是实现子节点所有被选中