Question

Let’s say I have two DataTables DT1 and DT2 with a single row.

DT1 has 3 columns: Col1, Col2, and Col3

and

DT2 has 2 columns: ColA, ColB.

Is it possible to join these two DataTables horizontally so I get Col1, Col2, Col3, ColA, and ColB?

Answer 1

I thin you have to add new columns and copy data either in third table or in one of the existing table

    DataTable dt1 = new DataTable();

    dt1.Columns.Add("col1", typeof(string));
    dt1.Columns.Add("col2", typeof(string));
    dt1.Columns.Add("col3", typeof(string));

    DataTable dt2 = new DataTable();

    dt2.Columns.Add("cola", typeof(string));
    dt2.Columns.Add("colb", typeof(string));

    object[] row = {'1', '2', '3'};
    dt1.Rows.Add(row);

    object[] row1 = { 'a', 'b' };
    dt2.Rows.Add(row1);

    // Create columns in dt1
    dt1.Columns.Add("cola", typeof(string));
    dt1.Columns.Add("colb", typeof(string));

    // Copy data from dt2
    dt1.Rows[0]["cola"] = dt2.Rows[0]["cola"];
    dt1.Rows[0]["colb"] = dt2.Rows[0]["colb"];