<asp:TreeView ID="TreeView1" Runat="server" DataSourceID="XmlDataSource1" οnclick="client_OnTreeNodeChecked();" ShowCheckBoxes="all">

<DataBindings>

<script language="javascript" type="text/javascript">

function client_OnTreeNodeChecked()

{

var obj = window.event.srcElement;

var treeNodeFound = false;

var checkedState;

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

var treeNode = obj;

checkedState = treeNode.checked;

do

{

obj = obj.parentElement;

} while (obj.tagName != "TABLE")

var parentTreeLevel = obj.rows[0].cells.length;

var parentTreeNode = obj.rows[0].cells[0];

var tables = obj.parentElement.getElementsByTagName("TABLE");

var numTables = tables.length

if (numTables >= 1)

{

for (i=0; i < numTables; i++)

{

if (tables[i] == obj)

{

treeNodeFound = true;

i++;

if (i == numTables)

{

return;

}

}

if (treeNodeFound == true)

{

var childTreeLevel = tables[i].rows[0].cells.length;

if (childTreeLevel > parentTreeLevel)

{

var cell = tables[i].rows[0].cells[childTreeLevel - 1];

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

inputs[0].checked = checkedState;

}

else

{

return;

}

}

}

}

}

}

</script>