获取两个DataTable之间的差集、交集、并集集合(Except、Intersect、Union)

//获取第一个数据源DataTable
DataTable dt1 = DBHelper.GetDataTable(“select top 10 ksdid,user_id,user_pwd from ksd_user_info”);

    IEnumerable query1 = dt1.AsEnumerable().Where(t => t.Field("user_id").StartsWith("66")).ToList();
    //获取第二个数据源DataTable
    DataTable dt2 = query1.CopyToDataTable();
   
    /*
    //比较两个数据源的交集
    IEnumerable query2 = dt1.AsEnumerable().Intersect(dt2.AsEnumerable(), DataRowComparer.Default);
    //两个数据源的交集集合      
    DataTable dt3 = query2.CopyToDataTable();
   
   如果是不同结构的表
         //比较两个数据源的交集
            var intersectUser = from r in bgdt.AsEnumerable()
                                where
                                    (from rr in bgdt1.AsEnumerable() select rr.Field("TechnologyName")).Contains(
                                    r.Field("TechnologyName"))
                                    
                                select r;

    //获取两个数据源的并集
    IEnumerable query2 = dt1.AsEnumerable().Union(dt2.AsEnumerable(), DataRowComparer.Default);
    //两个数据源的并集集合
    DataTable dt3 = query2.CopyToDataTable();
      

    //获取两个数据源的差集
    IEnumerable query2 = dt1.AsEnumerable().Except(dt2.AsEnumerable(), DataRowComparer.Default);
    //两个数据源的差集集合
    DataTable dt3 = query2.CopyToDataTable();

不同结构的表：
var normalReceive = from r in dtUser.AsEnumerable()
where
!(from rr in dtDND.AsEnumerable() select rr.Field(“username”)).Contains(
r.Field(“username”))
select r;

*/
求两个数组之间的交集
string daterange1 = “2010-1-3 2010-4-1/2010-5-1 2010-7-1/2010-9-10/2010-10-30 2010-11-10”;
string daterange2 = “2010-2-1 2010-3-2/2010-6-1 2010-8-10/2010-9-1 2010-9-20/2010-10-2 2010-10-7/2010-10-30 2010-11-10”;

        string[] date1 = daterange1.Split('/');
        string[] date2 = daterange2.Split('/');

        //string[] jiaoji = date1.Intersect(date2).ToArray();