ممكن حل مشكلة من جديد اخواني كرام لزال يوجد تكرار في بيانات
string selectedInvoiceNumber = dataGridView2.SelectedRows[0].Cells[0].Value.ToString();
string query = @"
SELECT
i.invoice_number,
i.invoice_date,
i.customer_name,
d.item_name,
d.quantity,
d.unit_price,
i.total_amount,
i.total_ar,
d.store_number
FROM
Invoices i
INNER JOIN InvoiceDetails d ON i.invoice_number = d.invoice_number
WHERE
i.invoice_number = @invoice_number
";
DataTable dt = new DataTable();
SqlCommand cmd = new SqlCommand(query, Class1.sqlCon);
cmd.Parameters.AddWithValue("@invoice_number", selectedInvoiceNumber);
SqlDataAdapter adp = new SqlDataAdapter(cmd);
adp.Fill(dt);
CrystalReport4 cr = new CrystalReport4();
cr.SetDataSource(dt);
prev pp = new prev();
pp.crystalReportViewer1.ReportSource = cr;
pp.crystalReportViewer1.Refresh();
pp.Show();