How to join two DataTables

How to join two DataTables using C#

I have found out the way to get the join of the tables using the GetParentRow() method in combination with a "Relation" in the DataSet.

Here is the code:

DataTable dt1 = new DataTable("Table1");

DataTable dt2 = new DataTable("Table2");

DataSet ds = new DataSet("DataSet");

dt1.Columns.Add("Eno", typeof(Int32));

dt1.Columns.Add("Ename", typeof(String));

dt1.Columns.Add("Salary", typeof(Double));

dt1.Columns.Add("Deptno", typeof(Int32));

dt1.PrimaryKey = new DataColumn[] { dt1.Columns["Eno"] };

dt2.Columns.Add("Deptno", typeof(Int32));

dt2.Columns.Add("Dname", typeof(String));

dt2.PrimaryKey = new DataColumn[] { dt2.Columns["Deptno"] };

ds.Tables.Add(dt1);

ds.Tables.Add(dt2);

// Loading data into dt1, dt2:

object[] o1 ={ 1, "dvs.kiran kumar", 50000.50, 10 };

object[] o2 ={ 2, "Raj", 4000.50, 20 };

object[] o3 ={ 3, "Gary", 10000.50, 10 };

object[] c1 ={ 10, "MFG" };

object[] c2 ={ 20, "EAS" };

object[] c3 ={ 30, "E&U" };

object[] c4 ={ 40, "PES" };

dt2.Rows.Add(c1);

dt2.Rows.Add(c2);

dt2.Rows.Add(c3);

dt2.Rows.Add(c4);

dt1.Rows.Add(o1);

dt1.Rows.Add(o2);

dt1.Rows.Add(o3);

DataRelation drel = new DataRelation("EquiJoin", dt2.Columns["Deptno"], dt1.Columns["Deptno"]);

ds.Relations.Add(drel);

DataTable jt = new DataTable("Joinedtable");

jt.Columns.Add("Eno", typeof(Int32));

jt.Columns.Add("Ename", typeof(String));

jt.Columns.Add("Salary", typeof(Double));

jt.Columns.Add("Deptno", typeof(Int32));

jt.Columns.Add("Dname", typeof(String));

ds.Tables.Add(jt);

foreach (DataRow dr in ds.Tables["Table1"].Rows)

{

       DataRow parent = dr.GetParentRow("EquiJoin");

       DataRow current = jt.NewRow();

       // Just add all the columns' data in "dr" to the New table.

       for (int i = 0; i < ds.Tables["Table1"].Columns.Count; i++)

       {

             current[ i ] = dr[ i ];

       }

       // Add the column that is not present in the child, which is present in the parent.

       current["Dname"] = parent["Dname"];

       jt.Rows.Add(current);

}

dataGridView1.DataSource = ds.Tables["Joinedtable"];