程序段中对语句作了说明。主要使用xmlwriter类进行xml文件生成。
下面这是由关系数据库生成相应xml文件过程。由于xml只是中间件，所以忽略了schema或者dtd。
 1        private void page_load(object sender, system.eventargs e)
 2        {
 3            // 在此处放置用户代码以初始化页面
 4            //基本信息定义
 5            string strtablename="systypes";
 6            string strconnection="server=suntears;user id=sa;password=041210;database=webapplication1_db";
 7            string strsql="select * from "+strtablename;
 8            sqlconnection objconn=new sqlconnection(strconnection);
 9            sqldataadapter objadapter=new sqldataadapter(strsql,objconn);
10            dataset objdset=new dataset();
11            objadapter.fill(objdset,"temp");
12            xmltextwriter objxmlwriter;
13            string strtemp1=request.physicalapplicationpath;
14            string strpath=strtemp1+"qiming.xml";
15            //初始化xmlwriter.用此类写xml文件
16            objxmlwriter=new xmltextwriter(strpath,null);
17            //创建开头的xml声明
18            objxmlwriter.writestartdocument();
19            //创建根元素xml1
20            objxmlwriter.writestartelement("xml1");
21            //表名为元素名，字段名为属性，表中的记录为属性的值
22            for(int i=0;i<objdset.tables["temp"].rows.count;i++)
23            {
24            objxmlwriter.writestartelement("menu");
25                for(int j=0;j<objdset.tables["temp"].columns.count;j++)
26                {
27                    //写入属性
28                    objxmlwriter.writeattributestring(objdset.tables["temp"].columns[j].columnname,objdset.tables["temp"].rows[i][j].tostring());
29                }
30                objxmlwriter.writeendelement();
31            }
32            objxmlwriter.writeendelement();
33            objxmlwriter.writeenddocument();
34            //用close方法关闭文件，否则文件将被锁定
35            objxmlwriter.close();
36            // 在页面上显示结果
37            string strxmlresult;
38            streamreader objsr = file.opentext(strpath);
39            strxmlresult = objsr.readtoend();
40            objsr.close();
41            response.write("<pre>" + server.htmlencode(strxmlresult) + "<pre>");
42        }
下面是通过上面程序生成的xml文件生成关系数据库的代码

 1        private void page_load(object sender, system.eventargs e)
 2        {
 3            // 在此处放置用户代码以初始化页面
 4            //基本信息定义
 5            int cx=1;
 6            string strconn="server=suntears;user id=sa;password=;database=xml_example";
 7            string strappstr=request.physicalapplicationpath;
 8            string strpath=strappstr+"qiming.xml";
 9            string strtablename="xml1";
10            string strcreatetable="create table "+strtablename+"(";
11            xmltextreader objxmlreader=new xmltextreader(strpath);
12            sqlconnection objconn=new sqlconnection(strconn);
13            sqlcommand objcommand;
14            sqldataadapter objadapter;
15            dataset objdset=new dataset();
16            datarow objrow;
17            xmlnodetype objnodetype;
18            //采用xmlreader类进行xml文件访问操作
19            //xmlreader采用拉（pull）模式。因此通过read()方法迭代各个节点
20            while(objxmlreader.read())
21            {
22                objnodetype=objxmlreader.nodetype;
23                //根据节点类型进行不同操作
24                switch(objnodetype)
25                {
26                    //xml文件开头的声明
27                    case xmlnodetype.xmldeclaration:
28                        response.write("11111"+objxmlreader.name+"<br>");
29                        break;
30                    //正常节点类型
31                    case xmlnodetype.element:
32                        //根据属性个数判断是否是根元素
33                        if(objxmlreader.attributecount>0)
34                        {
35                            //cx作为标志位。第一次访问非根元素节点时根据元素结构生成数据库
36                            if(cx==1)
37                            {
38                                while(objxmlreader.movetonextattribute())
39                                {
40                                    strcreatetable=strcreatetable+objxmlreader.name+" varchar(50), ";
41                                }
42                                strcreatetable=strcreatetable+")";
43                                objcommand=new sqlcommand(strcreatetable,objconn);
44                                objconn.open();
45                                objcommand.executenonquery();
46                                objconn.close();
47                                objadapter=new sqldataadapter("select * from "+strtablename,objconn);
48                                objadapter.fill(objdset,strtablename);
49                                objxmlreader.movetofirstattribute();
50                                //更改标志为cx数值
51                                cx=0;
52                            }
53                            //将xml文件中数据转存到dataset对象中
54                            objrow=objdset.tables[strtablename].newrow();
55                            objxmlreader.movetofirstattribute();
56                            for(int j=0;j<objxmlreader.attributecount;j++)
57                            {
58                                objrow[j]=objxmlreader.value.tostring();
59                                objxmlreader.movetonextattribute();
60                            }
61                            objdset.tables[strtablename].rows.add(objrow);
62                        }
63                        break;
64                }
65            }
66            //显示转存后的数据表
67            datagrid1.datasource=objdset.tables[strtablename];
68            datagrid1.databind();
69        }将数据更新到数据库的代码没有编写，自己弄吧^_^

http://suntears.cnblogs.com/archive/2006/06/02/416207.html