Devexpress ASP.NET中ASPxTreeList节点的拖动

<dx:ASPxTreeList Width="400" ID="trlcustom" ClientInstanceName="trlcustom" ClientIDMode="Static" runat="server" AutoGenerateColumns="False"
KeyFieldName="DeptID" ParentFieldName="Parent" OnProcessDragNode="trlcustom_ProcessDragNode" OnInit="trlcustom_Init">
<Columns>
<dx:TreeListTextColumn FieldName="DeptName" VisibleIndex="0">
</dx:TreeListTextColumn>
<dx:TreeListTextColumn FieldName="Parent" VisibleIndex="1">
</dx:TreeListTextColumn>
</Columns>
<SettingsSelection AllowSelectAll="True" Enabled="True" Recursive="True" />
<Settings VerticalScrollBarMode="Visible" ScrollableHeight="300" />
<SettingsBehavior AutoExpandAllNodes="true" AllowDragDrop="true" AllowFocusedNode="true" />
<SettingsEditing AllowNodeDragDrop="true" />
</dx:ASPxTreeList>

/// <summary>
/// 绑定数据
/// </summary>
private void BindTreeList()
{
string sql = "select * from T_Dept";
dbclass.sql = sql;
DataSet dv = new DataSet();
dv = dbclass.Executeds();//只是查询填充
trlcustom.DataSource = dv;
trlcustom.DataBind();
}

/// <summary>
/// 树的init方法
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void trlcustom_Init(object sender, EventArgs e)
{
BindTreeList();
}

/// <summary>
/// 节点的拖动
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void trlcustom_ProcessDragNode(object sender, DevExpress.Web.ASPxTreeList.TreeListNodeDragEventArgs e)
{
int dragDeptID = Convert.ToInt32(e.Node["DeptID"].ToString());
int dragDeptIDParent = Convert.ToInt32(e.Node["Parent"].ToString());
int dropDeptID = Convert.ToInt32(e.NewParentNode["DeptID"].ToString());
dbclass.sql = "update T_Dept set Parent= " + dropDeptID.ToString() + " where DeptID= " + dragDeptID.ToString();
if (!dbclass.executesql())
{
e.Handled = true;
return;
}
else
{
e.Handled = true;
BindTreeList();
}
}