尝试从datagridview中删除所选行，但它正在删除多行

Question

It is a simple question, but since I am new to C#, I am not sure how to solve this. Basically, I have a datagridview that displays records from MySQL table. I have a delete button, which by clicking performs the sql query, which is working fine, and is also meant to then delete the selected row from datgridview. But what actually happening, is it deletes multiple rows even when only one row is selected. Here is the query:

    private void delete_btn_Click(object sender, EventArgs e)
    {
        foreach (DataGridViewRow row in dataGridView1.Rows)
        {
            string constring = @"server = localhost; user id = root; password = pass; persistsecurityinfo = false; database = mapping; allowuservariables = false";
            using (MySqlConnection con = new MySqlConnection(constring))
            {
                using (MySqlCommand cmd = new MySqlCommand("UPDATE deletion SET date_time = UTC_TIMESTAMP() where product_id =" + proid_txtbx.Text, con))
                {
                    cmd.Parameters.AddWithValue("@product_id", row.Cells["product_id"].Value);
                    cmd.Parameters.AddWithValue("@product_name", row.Cells["product_name"].Value);
                    cmd.Parameters.AddWithValue("@category_id", row.Cells["category_id"].Value);
                    cmd.Parameters.AddWithValue("@date_time", row.Cells["date_time"].Value);
                    con.Open();
                    cmd.ExecuteNonQuery();
                }
                foreach(DataGridViewRow item in this.dataGridView1.SelectedRows)
                {
                   dataGridView1.Rows.RemoveAt(this.dataGridView1.SelectedRows[0].Index);
                }
            }
        }

Screenshots: Row 6 should be deleted: Other Rows are deleted when I click Delete button

Answer 1

I think your problem is with your foreach loop. You are looping through all your rows with dataGridView1.Rows . Tr dataGridView1.SelectedRows instead:

foreach (DataGridViewRow row in dataGridView1.SelectedRows)
    if (!row.IsNewRow) dataGridView1.Rows.Remove(row);

Answer 2

How about creating new command, somethnig like...

DELETE FROM YourTable WHERE product_id = ?

After that you can get value of selected item index:

int product_id = Convert.ToInt32(DataGridView1.SelectedRows[0].Cells[0].Value)

And at the end run the command and pass it the product_id int you got from command. I think it should work without problems...

Answer 3

You can use:

private void delete_btn_Click(object sender, EventArgs e)
{
   //Works even when whole row is selected.
   int rowIndex = datagridview.CurrentCell.RowIndex;

   //You can also then easily get column names / values on that selected row
   string product_id = datagridview.Rows[rowIndex].Cells["Column Name Here"].Value.ToString();

   //Do additional logic

   //Remove from datagridview.
   datagridview.Rows.RemoveAt(rowIndex);

}