Question

I’m creating winForm app,In that Onbutton click i gather Data Tables from of Two database Mysql and Sqlite database.
I getting Casting error while on casting Linq query to IEnumerable to make fetch query values to DataTable to make display in DataGrid view.

private void button1_Click(object sender, EventArgs e)
{

    var obj = new table1TableAdapter();  //Mysql Table Adapter
    var obj2 = new Table1TableAdapter(); // Sqlite Table Adapter
    var ds = new DataSet();
    ds.Tables.Add(obj.GetData());
    ds.Tables.Add(obj2.GetData());
    var tab1 = ds.Tables[0];
    var tab2 = ds.Tables[1];
    var query = from o in tab1.AsEnumerable()
                join od in tab2.AsEnumerable()
                on o.Field<string>("Name") equals od.Field<string>("Name")
                select new
                {
                    Name = o.Field<string>("Name"),
                    Rollno = od.Field<Int64>("rollno"),
                    Book = o.Field<string>("Book")
                };

    var q2 = (IEnumerable<DataRow>)query; //Unable to cast object of type <JoinIterator>

    DataTable orderTable = q2.CopyToDataTable();
    dataGridView1.DataSource = orderTable;
}

Answer 1

Looking at your code, I’d say, why cast it to IEnumerable<DataRow> at all ? Just simply bind the query to your GridView.

dataGridView1.DataSource = query.ToList();