CRUD在C＃中使用Datagridview

Question

I have got an error information when I tried to execute my coding program in C#. I try to Insert the data using datagridview in C# but when I tried, I have got this error information. "An unhandled exception of type 'Oracle.DataAccess.Client.OracleException' occurred in Oracle.DataAccess.dll Additional information: External component has thrown an exception" . Here is my coding program;

private void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
    {
        INST_NO = dataGridView1.Rows[e.RowIndex].Cells["INST_NO"].Value.ToString();

        if (INST_NO == "")
        {
            INST_NO1 = 0;
        }
        else
        {
              INST_NO1 = Convert.ToInt32(dataGridView1.Rows[e.RowIndex].Cells["INST_NO"].Value.ToString());
        }
        if (INST_NO1 == 0)
        {
            OracleCommand cmd = conn.CreateCommand();
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = "INSERT INTO TMCI_IM_PROD VALUES('" + dataGridView1.Rows[e.RowIndex].Cells["INST_NO"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["ITM_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["LINE_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_LOC_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_SCHD_QTY"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_ST_SCHD_DT"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_END_SCHD_DT"].Value.ToString() + "','" + dataGridView1.Rows[e.RowIndex].Cells["ORD_STS_TYP"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["CAVITY"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["RESULT_1"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["RESULT_2"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["TRANSFER_1"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["TRANSFER_2"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["INS_TS"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["INS_USR_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["UPD_TS"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["UNIT_WT"].Value.ToString() + "')";
            cmd.ExecuteNonQuery();
            fill_grid();
        }
        else
        {
            OracleCommand cmd = conn.CreateCommand();
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = "UPDATE TMCI_IM_PROD SET INST_NO='" + dataGridView1.Rows[e.RowIndex].Cells["ITM_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["LINE_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_LOC_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_SCHD_QTY"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_ST_SCHD_DT"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["PROD_END_SCHD_DT"].Value.ToString() + "','" + dataGridView1.Rows[e.RowIndex].Cells["ORD_STS_TYP"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["CAVITY"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["RESULT_1"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["RESULT_2"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["TRANSFER_1"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["TRANSFER_2"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["INS_TS"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["INS_USR_CD"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["UPD_TS"].Value.ToString() + "', '" + dataGridView1.Rows[e.RowIndex].Cells["UNIT_WT"].Value.ToString() + "' WHERE INST_NO=" + INST_NO1 + "";
            cmd.ExecuteNonQuery();
            fill_grid();
        }

    }

I have tried with many other ways, but I did not find it, how to overcome this problem. Does anyone here could help me to solve this problem? Thank you in advance.

Answer 1

This isn't the way a datagridview is supposed to be used, but to explain it properly would quite a large undertaking. Basically, datagridview shouldn't be used as a storage of data, it should just be connected to a datasource (a DataTable)and that is the data storage container. You just use the DGV as a device for the user to click on, type in etc to change the data in the datatable, and then you use a tableadapter to send the updates back to the database. Go here: https://msdn.microsoft.com/en-us/library/fxsa23t6.aspx and start by doing the "Creating a Simple Data Application" tutorial

This way your app ends up a better representation of MVC theory - model is the datatable, view (a device that shows data) and control (a device that changes data) is done by the datagridview