服务器端树状结构如何在客户端显示？

需求：服务器端树状结构，客户端通过web service 读取该结构并显示。

方案：服务器端从资料库读取树状结构生成XML文档，以XML形式通过web service 发送到客户端。客户端解析XML文档生成树状结构

1、服务器端代码

如何建立 web service 不再详述。Web Service 分段上传大文件 一文中有详细描述。

 

[WebMethod(EnableSession=true)]  
public XmlDocument GetWMFolder()
{            
    XmlDocument XmlSend = new XmlDocument();
    XmlElement ParentNode;
    XmlSend = new XmlDocument();
    ParentNode = Xml.CreateElement(szName);
    Xml.AppendChild(ParentNode);
   
    ParentNode = XmlSend.CreateElement("WMFolder");
    GetEIPWMFolder(0, ParentNode);
    XmlSend.DocumentElement.AppendChild(ParentNode);                      
            
    return XmlSend;
        

}
private void GetEIPWMFolder(int iWMFolderID, XmlElement ParentNode)
{
    int i, iFolderID;
    string szSql, szTitle;
    DataTable RS;            
    XmlElement NewNode;

    szSql = "select * from WMFolder where ParentID =" + iWMFolderID +" order by ViewOrder asc";
    //Get Tatatable
     RS = C.Comm.GetRecordSet(PagePara, szSql);
          
    for (i = 0; i < RS.Rows.Count; i++)
    {

         iFolderID = C.Comm.RSInt(PagePara,RS, i, "WMFolderID");
         szTitle = C.Comm.RSString(PagePara, RS, i, "Title");
         NewNode = XmlSend.CreateElement("_"+szTitle);
         SetAttr(NewNode, "Title", szTitle);
         SetAttr(NewNode, "WMFolderID", iFolderID);
         ParentNode.AppendChild(NewNode);
         GetEIPWMFolder(iFolderID, NewNode);
    }
}       
private void SetAttr(XmlElement Node, string szAttrName, object Value)
{
    Node.SetAttribute(szAttrName, "", Value.ToString());
}

 

2、客户端代码

private void LoadTree()
{            
    XmlNode XmlRecv;
    XmlElement RecvAction, RecvWMFolder;
    XmlNodeList TheWMFolder;

    tvWMFolder.Nodes.Clear();
    XmlRecv =HpService.GetWMFolder();
    try
    {
         RecvAction = (XmlElement)XmlRecv.FirstChild;
    }
    catch
    {
        RecvAction = null;
    }

    if (RecvAction == null)
    {
        return;
    }
    TheWMFolder = RecvAction.ChildNodes;
    for (int i = 0; i < TheWMFolder.Count; i++)
    {
        RecvWMFolder = (XmlElement)TheWMFolder.Item(i);
        LoadEIPWMFolder(RecvWMFolder, null);
    }

}
private void LoadEIPWMFolder(XmlElement WMFolderNode, TreeNode ParentNode)
{
    int i, iWMFolderID;
    string szTitle;
    XmlElement RecvDataRow;
    XmlNodeList TheChildNodes;
    TreeNode NewNode;

    TheChildNodes = WMFolderNode.ChildNodes;
    for (i = 0; i < TheChildNodes.Count; i++)
    {
        RecvDataRow = (XmlElement)TheChildNodes.Item(i);

        iWMFolderID = (int)GetAttr(RecvDataRow, "WMFolderID",0);
        szTitle = GetAttr(RecvDataRow, "Title","");
        NewNode = new TreeNode(szTitle);                
        NewNode.Tag = iWMFolderID;

        if (ParentNode == null)
        {
              tvWMFolder.Nodes.Add(NewNode);
              LoadEIPWMFolder(RecvDataRow, NewNode);
        }
        else
        {
            ParentNode.Nodes.Add(NewNode);
            LoadEIPWMFolder(RecvDataRow, NewNode);
        }
    }
}
public static string GetAttr(XmlElement Node, string szAttrName, string szDefValue)
{
    string szValue;

    if ((Node != null) && (Node.Attributes[szAttrName] != null))
        szValue = Node.Attributes[szAttrName].Value;
    else
        szValue = szDefValue;
   
      return szValue;

}