C# 写XML例子,根据行政代码树生成XML

Db_Class DbClass;
XmlTextWriter tw;
//填充一个子项
private void FillOneXml(string Sqlstr, int leveled)
{
int num = Convert.ToInt16(DbClass.Db_Executequery("select count(*) from (" + Sqlstr + ")"));
if (num < 1) return;
OracleDataReader DataReader = DbClass.Db_CreateReader(Sqlstr);
try
{
while (DataReader.Read())
{
string objid = DataReader[0].ToString();
string objName = (string)DataReader[1];
tw.WriteStartElement("cantoncode" + leveled);
tw.WriteAttributeString("cantoncode", objid);
tw.WriteAttributeString("cantonname", objName);
Sqlstr = " Select cantoncode,cantonName from nc_cantoncode "+ " where parentcode =" + objid + " order by cantoncode";
FillOneXml(Sqlstr, leveled + 1);
tw.WriteEndElement();
}

}
finally
{
DataReader.Close();
}

}

private void button1_Click(object sender, EventArgs e)
{
DbClass = new Db_Class();
DbClass.Db_Conn();
try
{
string fileName = @"C:/cantoncode.xml";
tw = new XmlTextWriter(fileName, null);
tw.Formatting = Formatting.Indented;
tw.WriteStartDocument();
tw.WriteStartElement("cantoncode");
string Sqlstr = " Select cantoncode,cantonName from nc_cantoncode "
+ " where parentcode is null order by cantoncode ";
FillOneXml(Sqlstr, 1);
tw.WriteEndElement();
tw.WriteEndDocument();
tw.Flush();
tw.Close();
}
finally
{
DbClass.close();
}

}

//测试 闫磊 Email:Landgis@126.com,yanleigis@21cn.com 2006.10.11