javascrip实现：若选中TreeView的父节点checkbox，则其子节点全部选中；子节点全部没选中，则父节点也会没选中。

    <script type="text/javascript">
        function public_GetParentByTagName(element, tagName) {
            var parent = element.parentNode;
            var upperTagName = tagName.toUpperCase();
            //如果这个元素还不是想要的tag就继续上溯
            while (parent && (parent.tagName.toUpperCase() != upperTagName)) {
                parent = parent.parentNode ? parent.parentNode : parent.parentElement;
            }
            return parent;
        }

        //设置节点的父节点Cheched——该节点可访问，则他的父节点也必能访问 
        function setParentChecked(objNode) {
            var objParentDiv = public_GetParentByTagName(objNode, "div");
            if (objParentDiv == null || objParentDiv == "undefined") {
                return;
            }
            var objID = objParentDiv.getAttribute("ID");
            objID = objID.substring(0, objID.indexOf("Nodes"));
            objID = objID + "CheckBox";
            var objParentCheckBox = document.getElementById(objID);
            if (objParentCheckBox == null || objParentCheckBox == "undefined") {
                return;
            }
            if (objParentCheckBox.tagName != "INPUT" && objParentCheckBox.type == "checkbox")
                return;
            objParentCheckBox.checked = true;
            setParentChecked(objParentCheckBox);
        }

        function setParentUnChecked(objNode) {
            var objParentDiv = public_GetParentByTagName(objNode, "div");
            if (objParentDiv == null || objParentDiv == "undefined") {
                return;
            }
            var objID = objParentDiv.getAttribute("ID");
            objID = objID.substring(0, objID.indexOf("Nodes"));
            objID = objID + "CheckBox";
            var objParentCheckBox = document.getElementById(objID);
            if (objParentCheckBox == null || objParentCheckBox == "undefined") {
                return;
            }
            if (objParentCheckBox.tagName != "INPUT" && objParentCheckBox.type == "checkbox")
                return;
            objParentCheckBox.checked = GetChildUnChecked(objParentDiv);
            setParentUnChecked(objParentCheckBox);
        }

        function GetChildUnChecked(divID) {
            var objchild = divID.getElementsByTagName("INPUT");
            var count = objchild.length;
            for (var i = 0; i < objchild.length; i++) {
                var tempObj = objchild[i];
                if (tempObj.type == "checkbox") {
                    if (tempObj.checked == true) return true;
                }
            }
            return false;
        }
        
        //设置节点的子节点cheched——该节点可以访问，则他的子节点也都能或不能访问 
        function setChildChecked(divID, objNode) {
            var objchild = divID.getElementsByTagName("INPUT"); ;
            var count = objchild.length;
            for (var i = 0; i < objchild.length; i++) {
                var tempObj = objchild[i];
                if (tempObj.type == "checkbox") {
                    tempObj.checked = objNode.checked;                    
                }
            }
        }
        function CheckEvent() {

            var objNode = event.srcElement;

            if (objNode.tagName != "INPUT" || objNode.type != "checkbox")
                return;

            if (objNode.checked == true) {
                setParentChecked(objNode);
                var objID = objNode.getAttribute("ID");
                var objID = objID.substring(0, objID.indexOf("CheckBox"));
                var objParentDiv = document.getElementById(objID + "Nodes");
                if (objParentDiv != null && objParentDiv != "undefined") {
                    setChildChecked(objParentDiv, objNode);
                }
            }
            else {
                setParentUnChecked(objNode);
                var objID = objNode.getAttribute("ID");
                var objID = objID.substring(0, objID.indexOf("CheckBox"));
                var objParentDiv = document.getElementById(objID + "Nodes");
                if (objParentDiv != null && objParentDiv != "undefined") {
                    setChildChecked(objParentDiv, objNode);
                }
            }

        }
    </script>

this.tvlist.Attributes.Add("onclick", "CheckEvent()");