<link  rel="stylesheet"  href="Js/ext-4.2/resources/css/ext-all-neptune.css"/>

    <script src="Js/jQuery/jquery-1.8.2.min.js" type="text/javascript"></script>

    <script src="Js/ext-4.2/ext-all-dev.js" type="text/javascript"></script> 

    <script type="text/javascript">

        var tree;

        $(document).ready(function() {

            //Ext.create('Ext.tree.Panel', {  });

            tree = new Ext.tree.TreePanel({

                renderTo: 'tree1',

                title: 'Simple Tree',

                multiSelect: true,

                width: 200,

                height: 450,

                viewConfig: {

                    onCheckboxChange: function(e, t) {

                        var item = e.getTarget(this.getItemSelector(), this.getTargetEl()), record;

                        if (item) {

                            record = this.getRecord(item);

                            var check = !record.get('checked');

                            //getSelectedNodes()

                            record.set('checked', check);

                            if (check) {

                                record.bubble(function(parentNode) {

                                    parentNode.set('checked', true);

                                });

                                record.cascadeBy(function(node) {

                                    node.set('checked', true);

                                });

                                //                                record.expand();  联动效果 自动收起 自动展开

                                //                                record.expandChildren();

                            } else {

                                //                                record.collapse();

                                //                                record.collapseChildren();

                                record.cascadeBy(function(node) {

                                    node.set('checked', false);

                                });

                                record.bubble(function(parentNode) {

                                    var childHasChecked = false;

                                    var childNodes = parentNode.childNodes;

                                    if (childNodes || childNodes.length > 0) {

                                        for (var i = 0; i < childNodes.length; i++) {

                                            if (childNodes[i].data.checked) {

                                                childHasChecked = true;

                                                break;

                                            }

                                        }

                                    }

                                    if (!childHasChecked) {

                                        parentNode.set('checked', false);

                                    }

                                });

                            }

                        }

                    }

                },

                root: {

                    text: 'Root',

                    expanded: true, //是否展开子节点，默认为false

                    checked: true,

                    children: [

                                { id: '1', text: 'Child 1', checked: true, leaf: true },

                                { id: '2', text: 'Child 2', checked: true, leaf: true },

                                { id: '3', text: 'Child 3', checked: true, expanded: true, children: [{ id: '4', text: 'Grandchild', checked: true, leaf: true}] }

                              ]

                }

            });

            //窗体

            var win = new Ext.Window({

                title: '窗口',

                width: 476,

                height: 574,

                resizable: true,

                modal: true,

                closable: true,

                maximizable: true,

                minimizable: true,

                items: tree

            });

            win.show();

            var attr = tree.getChecked();

            for (var le = 0; le < attr.length; le++) {

                var json = eval(attr[le].getData());
　　　　　　　　　　　　json.text;

            }

        }); </script>