how to print multiple selected row from datagrid to crystal report

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C#

DataGridView

CrystalReports

Hi to all experts, i have a big problem here, i want to print data from my datagridview, when i select 1 row.. there is no problem, but when i try to print multiple row, just last selected row apear
here is the code :

private void button4_Click(object sender, EventArgs e)
        {
            ReportDocument report = new ReportDocument();
            report.Load("katalogbarang.rpt");
            if (Kodetxt.Text == "")
            {

            }
            else
            {
                report.RecordSelectionFormula = "{katalog.id}= " + dg1.SelectedRows[0].Cells[9].Value + "";
            }
            PrintReport rpt = new PrintReport();
            rpt.crystalReportViewer1.ReportSource = report;
            rpt.crystalReportViewer1.Refresh();
            rpt.ShowDialog();
        }

this is my little condition

-------------------------------------------
|kodebarang | namabarang | jumlah | harga |
-------------------------------------------
|0121 | kolor | 3 | 2000 |
|0892 | panci | 1 | 10000 |
|9200 | kutang | 2 | 20000 |
|8989 | cangcut | 8 | 2500 |
|7890 | sapu | 1 | 3000 |
-------------------------------------------

when im selecting one row (left click)

|0121 | kolor | 3 | 2000 |

or when i randomly click (in condition i just click one row) there is no problem,
then i chose randomly and more than just one row, but which appear in crystal report only the first i click

i want report in my crystal report are like this

|9200 | kutang | 2 | 20000 |
|0892 | panci | 1 | 10000 |

or

|7890 | sapu | 1 | 3000 |
|0121 | kolor | 3 | 2000 |
|9200 | kutang | 2 | 20000 |

please someone help me... give me some code and tutorial to resolve my prob
thanks in advance