数据表连接 c# - 连接数据表

Question

How to use joins with dataTable? Since i am new to C#, I dont know why my code is not working. can anyone please look into this?

var result = from x in clientpos.AsEnumerable()
                     join y in exec_pos.AsEnumerable()
                     on new { X1 = x.Field<string>("ClientCode"), X2 = x.Field<string>("Symbol"),
                         X3 = x.Field<string>("Expirydate"), X4 = x.Field<string>("Strikeprice") , X5 = x.Field<string>("ClientCode") }
                     equals new { X1 = y.Field<string>("ClientCode"), X2 = y.Field<string>("Symbol"),
                         X3 = y.Field<string>("Expirydate"), X4 = y.Field<string>("Strikeprice") ,
                         X5 = y.Field<string>("ClientCode")
                     }
                     select x;

Answer 1

The join is in the format below. You can add addition WHERE to the query if you need to additional filtering.

var result = (from x in clientpos.AsEnumerable()
             join y in exec_pos.AsEnumerable() on x.Field<string>("ClientCode") equals y.Field<string>("ClientCode")
             select new { client = x, exec = y}).ToList();