asp.net mvc 的ext tree第一次加载子节点不出来，刷新多次才可以

NealShi 2010-11-06 08:13:53

问题描述：asp.net mvc 的ext tree大多数情况下子节点第一次加载不出来，刷新才可以，有时候刷新好几次子节点还是不出来，
ACTION代码如：

public JsonResult GetGuestBooks()   

        {   

            List<jsondata> jsdata = new List<jsondata>();   

            for (int i = 1; i < 5; i++)   

            {   

                jsondata jd = new jsondata();   

                jd.id = "num" + i;   

                jd.text = "节点" + i;   

                jd.leaf = false;   

                for (int j = 1; j < 3; j++)   

                {   

                    jsondata subjd = new jsondata();   

                    subjd.id = "sub" + j;   

                    subjd.text = "子节点" + j;   

                    subjd.leaf = true;   

                    jd.children.Add(subjd);   

                }   

                jsdata.Add(jd);   

            }   

           return Json(jsdata, JsonRequestBehavior.AllowGet);   

        }

用到的类代码：

public class jsondata   

    {   

        //定义jsondata类，存放节点数据   

        public string id;   

        public string text;   

        public bool leaf;   

        public List<jsondata> children = new List<jsondata>();//存放子节点   

    }

前台显示部分view代码：

<script type="text/javascript">   

            Ext.onReady(function () {   

                Ext.QuickTips.init();   

                var mytree = new Ext.tree.TreePanel({   

                    el: "grid",   

                    animate: true,   

                    title: "简单Extjs动态树",   

                    collapsible: true,   

                    enableDD: true,   

                    enableDrag: true,   

                    rootVisible: true,   

                    autoScroll: true,   

                    autoHeight: true,   

                    width: 150,   

                    lines: true,   

                    //这里简简单单的loader的几行代码是取数据的,很经典哦     

                    loader: new Ext.tree.TreeLoader({   

                    dataUrl: "http://localhost:1683/Home/GetGuestBooks"  

                    })   

                });   

  

                //根节点   

                var root = new Ext.tree.AsyncTreeNode({   

                    id: "root",   

                    text: "控制面板",   

                    expanded: true  

                });   

  

                mytree.setRootNode(root);   

                mytree.render(); //不要忘记render()下,不然不显示哦   

            })   

               

        </script>   

        <div id="grid"></div>

生成的JSON字符串是：
[{"id":"num1","text":"节点1","leaf":false,"children":[{"id":"sub1","text":"子节点1","leaf":true,"children":[]},{"id":"sub2","text":"子节点2","leaf":true,"children":[]}]},{"id":"num2","text":"节点2","leaf":false,"children":[{"id":"sub1","text":"子节点1","leaf":true,"children":[]},{"id":"sub2","text":"子节点2","leaf":true,"children":[]}]},{"id":"num3","text":"节点3","leaf":false,"children":[{"id":"sub1","text":"子节点1","leaf":true,"children":[]},{"id":"sub2","text":"子节点2","leaf":true,"children":[]}]},{"id":"num4","text":"节点4","leaf":false,"children":[{"id":"sub1","text":"子节点1","leaf":true,"children":[]},{"id":"sub2","text":"子节点2","leaf":true,"children":[]}]}]

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