用DataTable綁定TreeView的方法

 用DataTable綁定TreeView的方法:

1. 從數據庫讀取含父子關係列的表並填充到DataSet裏去
2. 創建一個關白聯，併爲DataSet添加該關聯，DataSet的Nested屬性必需爲true.
3. 取得該DataSet的XML描述，用XSLT將XML規則化.
4. 綁定TreeView.

 

表的內容描述如下:

表名：CATEGORIES
CategoryID	ParentCategoryID	CategoryName
2		1
3		2
4		3
5	2	1.1
6	2	1.2
7	2	1.3
8	3	2.1
9	3	2.2
10	4	3.1
11	5	1.1.1
12	5	1.1.2
13	10	3.1.1
14	13	3.1.1.1
15	14	3.1.1.1.1
16	14	3.1.1.1.2
17	14	3.1.1.1.3

 

填充DataSet

//Connection to database

OleDbConnection objConn=
new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=" + Server.MapPath("db.mdb")  + ";Persist Security Info=False"); 

//SQL query to get data from CATEGORIES table

OleDbCommand objCommand=new OleDbCommand("SELECT * FROM CATEGORIES",objConn);

//OleDbDataAdapter

OleDbDataAdapter objDa =new OleDbDataAdapter(objCommand);

//DataSet

DataSet ds=new DataSet("CATEGORIESDS");
 

//Fill DataSet

objDa.Fill(ds ,"CATEGORIES");

 添加關聯

//Create DataRelation

DataRelation drel=new DataRelation("CATEGORIES_RECURSIVE",
ds.Tables["CATEGORIES"].Columns["CategoryID"],
ds.Tables["CATEGORIES"].Columns["ParentCategoryID"]);
 

//Make sure relation is nested

drel.Nested =true;

 

//Add relation to DataSet's Relations collection

ds.Relations.Add(drel);

 

XML轉換

//XmlDocument to hold XML generated from DataSet

XmlDocument objDoc=new XmlDocument();

 

//Load XML

objDoc.LoadXml(ds.GetXml());

 

//Create XslTransform object

XslTransform objXSL=new XslTransform();

 

//Load XSLT stylesheet

objXSL.Load(Server.MapPath("transformationtemplate.xslt"));

 

//StringWriter to temporarily hold result of the transformation

StringWriter writer=new StringWriter();

 

//Apply transformation with no arguments and dump results to StringWriter.

objXSL.Transform(objDoc.CreateNavigator(),null,writer);

 

綁定TreeView

//Set TreeView's TreeNodeSrc property to get XML from StringWriter.

TreeView1.TreeNodeSrc =writer.ToString();

 

//Bind TreeView

TreeView1.DataBind();

 

//Close StringWriter

writer.Close();