从数据库获取构造树结构是ExtJS TreePanel的核心技术，常用方法是TreeStroe里配置proxy，这种方式的root成了一个不受控制的节点。
TreeStroe的root实际是一个层叠json数据，大部分情况是直接写一些简单数据，但在实际应用中必定是要从数据库读取的。我的方法是先用Ext.Ajax.request获取root数据形成TreeStroe。定义一个全局的TreeStroe名字是mTreeStore,用Ext.Ajax.request获得root数据。TreeStoreRefresh函数与此类似，将mTreeStore的root换为新值。TreePanel的rootVisible属性必须为true，增加一个节点单击事件显示节点的信息。
var mTreeStore = null;
Ext.Ajax.request({
async: false,
url: '/api/BasicData_API/GetBasicTablesTreeSource',
method: 'get',
success: function (response, options)
{
var TreeRoot = Ext.decode(response.responseText);
mTreeStore = Ext.create('Ext.data.TreeStore',
{
root: TreeRoot
});
},
failure: function (response, options)
{
//var responseArray = Ext.decode(response.responseText);
Ext.Msg.alert('服务器错误', '数据处理错误原因:\n\r' + response.responseText);
}
});
function TreeStoreRefresh()
{
Ext.Ajax.request({
async: false,
url: '/api/BasicData_API/GetBasicTablesTreeSource',
method: 'get',
success: function (response, options)
{
var TreeRoot = Ext.decode(response.responseText);
if (mTreeStore != null)
{
mTreeStore.setRoot(TreeRoot);
}
},
failure: function (response, options)
{
//var responseArray = Ext.decode(response.responseText);
Ext.Msg.alert('服务器错误', '数据处理错误原因:\n\r' + response.responseText);
}
});
}
Ext.define('TreeToolbarCls', {
extend: 'Ext.toolbar.Toolbar',
padding:'0 0 0 0',
items: [{
text: '刷新',
iconCls: 'refresh',
handler: TreeStoreRefresh,
height: 30,
width: 65
}]
});
Ext.define('U1TreeCls',
{
extend: 'Ext.tree.Panel',
xtype: 'U1Tree_xtype',
//title: '基础数据字典',
rootVisible: true,
width: 300,
store: mTreeStore,
scrollable: true,
tbar:Ext.create('TreeToolbarCls'),
listeners:
{
itemclick: NodeClick
}
});
function NodeClick(node, record, item, index, e, eOpts)
{
if (typeof (record.data) == "undefined")
{
return;
}
var message = Ext.String.format('Level={0}<br/>state={1}', record.data.Level, record.data.state);
Ext.Msg.alert("节点信息", message);
}
下面是后台C#代码
定义一个TreeNode类，包含TreePanel节点固有的一些属性，也可以任意扩充，利用这个可以自定义许多附加数据，如我在里面定义Level表示节点的级别。
[Authorize]
[RoutePrefix("api/BasicData_API")]
public class BasicData_APIController : ApiController
{
[Route("GetBasicTablesTreeSource")]
public HttpResponseMessage GetBasicTablesTreeSource(string condition = null)
{
List<TreeNode> lstF = new List<TreeNode>();
ZydAdonet z = ZydAdonet.Instance();
string s1 = "select TableName,title from BaseDataTables order by TableName";
string sqltext = s1;
DataTable dt1;
string ErrMes;
z.Sql2DTReadOnly(s1, out dt1, null, out ErrMes);
TreeNode tnd;
foreach (DataRow drx in dt1.Rows)
{
tnd = new TreeNode
{
id = drx["TableName"].ToString(),
text = drx["title"].ToString(),
Level = 1,
iconCls = "table_6",
state = drx["TableName"].ToString() + " OK",
leaf = true
};
lstF.Add(tnd);
}
TreeNode root = new TreeNode
{
text = "基础数据字典",
expanded = false,
iconCls = "folder_close",
Level = 0,
state = "RootOfTree",
leaf = true
};
if (lstF.Count > 0)
{
root.expanded = true;
root.leaf = false;
root.iconCls = "folder_open";
root.children = lstF;
}
string JsonStr;
JsonStr = JsonConvert.SerializeObject(root);
HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK, "value");
response.Content = new StringContent(JsonStr, Encoding.GetEncoding("UTF-8"), "application/json");
response.Headers.CacheControl = new CacheControlHeaderValue()
{
MaxAge = TimeSpan.FromMinutes(10)
};
return response;
}
}
internal class TreeNode
{
public string id { get; set; }
public string text { get; set; }
public string iconCls { get; set; }
public string state { get; set; }
public bool leaf { get; set; }
public int Level { get; set; }
public bool expanded { get; set; }
public List<TreeNode> children { get; set; }
}
在NodeClick函数中断可以监视到更多的信息：
最后的运行效果：
然后更改数据表里的数据，点“刷新”就实现了TreePanel节点的刷新。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。
