c# 将数据导出成指定xml格式

Dataset的WriteXml是按记录一条一条的写成XML，对应的，不可能给你写成分省市的，必须要自己写循环判断，自己构造xml

用select * from [TableName] order by PROVINCE, CITY, COUNTRY, TOWN这条语句查询出结果，这样记录是按省市乡镇依次排列的，读到DataTable里，再循环读取，当前记录与前一条记录进行比对，如果省市乡都一样就追加“<town name="" /> ”，如果省市一样，追加<country>,如果只是省一样，追加<city>,全部遍历一遍，构造xml字符串即可。

补充：
    protected void WriteXML()
    {
        DataTable dt = new YourClass().YourMethod();//你的类.你的方法
        string str = "<address>";
        for (int i = 0; i < dt.Rows.Count; i++)
        {
            if (i == 0)
            {
                str += "<province name=\"" + dt.Rows[i]["Province"].ToString() + "\">" +
                        "<city name=\"" + dt.Rows[i]["City"].ToString() + "\">" +
                            "<country name=\"" + dt.Rows[i]["Country"].ToString() + "\">" +
                                "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
            }
            else
            {
                if (dt.Rows[i]["Province"].ToString() == dt.Rows[i - 1]["Province"].ToString() &&
                    dt.Rows[i]["City"].ToString() == dt.Rows[i - 1]["City"].ToString() &&
                    dt.Rows[i]["Country"].ToString() == dt.Rows[i - 1]["Country"].ToString())
                {
                    str += "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
                }
                else if (dt.Rows[i]["Province"].ToString() == dt.Rows[i - 1]["Province"].ToString() &&
                    dt.Rows[i]["City"].ToString() == dt.Rows[i - 1]["City"].ToString())
                {
                    str += "</country>";

                    str += "<country name=\"" + dt.Rows[i]["Country"].ToString() + "\">" +
                                "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
                }
                else if (dt.Rows[i]["Province"].ToString() == dt.Rows[i - 1]["Province"].ToString())
                {
                    str += "</country>";
                    str += "</city>";

                    str += "<city name=\"" + dt.Rows[i]["City"].ToString() + "\">" +                                "<country name=\"" + dt.Rows[i]["Country"].ToString() + "\">" +
                                    "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
                }
                else
                {
                    str += "</province>";
                }

                if (i == dt.Rows.Count - 1)
                {
                    str += "</country>";
                    str += "</city>";
                    str += "</province>";
                }
            }
        }
        str += "</address>";
    }

结果如图
Dataset的WriteXml是按记录一条一条的写成XML，对应的，不可能给你写成分省市的，必须要自己写循环判断，自己构造xml

用select * from [TableName] order by PROVINCE, CITY, COUNTRY, TOWN这条语句查询出结果，这样记录是按省市乡镇依次排列的，读到DataTable里，再循环读取，当前记录与前一条记录进行比对，如果省市乡都一样就追加“<town name="" /> ”，如果省市一样，追加<country>,如果只是省一样，追加<city>,全部遍历一遍，构造xml字符串即可。

补充：
    protected void WriteXML()
    {
        DataTable dt = new YourClass().YourMethod();//你的类.你的方法
        string str = "<address>";
        for (int i = 0; i < dt.Rows.Count; i++)
        {
            if (i == 0)
            {
                str += "<province name=\"" + dt.Rows[i]["Province"].ToString() + "\">" +
                        "<city name=\"" + dt.Rows[i]["City"].ToString() + "\">" +
                            "<country name=\"" + dt.Rows[i]["Country"].ToString() + "\">" +
                                "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
            }
            else
            {
                if (dt.Rows[i]["Province"].ToString() == dt.Rows[i - 1]["Province"].ToString() &&
                    dt.Rows[i]["City"].ToString() == dt.Rows[i - 1]["City"].ToString() &&
                    dt.Rows[i]["Country"].ToString() == dt.Rows[i - 1]["Country"].ToString())
                {
                    str += "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
                }
                else if (dt.Rows[i]["Province"].ToString() == dt.Rows[i - 1]["Province"].ToString() &&
                    dt.Rows[i]["City"].ToString() == dt.Rows[i - 1]["City"].ToString())
                {
                    str += "</country>";

                    str += "<country name=\"" + dt.Rows[i]["Country"].ToString() + "\">" +
                                "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
                }
                else if (dt.Rows[i]["Province"].ToString() == dt.Rows[i - 1]["Province"].ToString())
                {
                    str += "</country>";
                    str += "</city>";

                    str += "<city name=\"" + dt.Rows[i]["City"].ToString() + "\">" +                                "<country name=\"" + dt.Rows[i]["Country"].ToString() + "\">" +
                                    "<town name=\"" + dt.Rows[i]["Town"].ToString() + "\" />";
                }
                else
                {
                    str += "</province>";
                }

                if (i == dt.Rows.Count - 1)
                {
                    str += "</country>";
                    str += "</city>";
                    str += "</province>";
                }
            }
        }
        str += "</address>";
    }

结果如图

说明：只支持一个省的，要是多个省的你再稍做改动