In this case I display values into datagridview from Projects table which it has only 2 columns:
PROJECT_NAME VARCHAR
ID INT // Which is hidden in datagridview, and as AUTOINCREMENT
I have already done with editing values in this table and it works fine:
`private void dataGridView4_CellEndEdit(object sender, DataGridViewCellEventArgs e)
{
string name_project = dataGridView4.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString();
string id = dataGridView4.Rows[e.RowIndex].Cells[0].Value.ToString();
MySqlConnection connection = new MySqlConnection("datasource = localhost; port = 3306; username = root; password = ");
MySqlCommand cmd = new MySqlCommand("UPDATE projekt1.projects SET PROJECTS_NAME = @PROJECTS_NAME WHERE ID = @ID", connection);
cmd.Parameters.Add("@ID", MySqlDbType.Int64).Value = int.Parse(id);
cmd.Parameters.Add("@PROJECTS_NAME", MySqlDbType.VarChar).Value = name_project;
try
{
connection.Open();
cmd.ExecuteNonQuery();
connection.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}`But i have a problem with inserting new row and saving automatically in database.
What i've tried?
1) I've tried with RowValidated Event:
private void dataGridView4_RowValidated(object sender, DataGridViewCellEventArgs e)
{
string name_project = dataGridView4.Rows[e.RowIndex].Cells[1].Value.ToString();
string id = dataGridView4.Rows[e.RowIndex].Cells[0].Value.ToString();
MySqlConnection connection = new MySqlConnection("datasource = localhost; port = 3306; username = root; password = ");
MySqlCommand cmd = new MySqlCommand("INSERT INTO projekt1.projects(PROJECT_NAME) VALUES(@NPROJECT_NAME);", connection);
cmd.Parameters.Add("@ID", MySqlDbType.Int64).Value = int.Parse(id);
cmd.Parameters.Add("@PROJECT_NAME", MySqlDbType.VarChar).Value = name_project;
try
{
connection.Open();
cmd.ExecuteNonQuery();
connection.Close();
MessageBox.Show("ok");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
try
{
connection.Open();
cmd.ExecuteNonQuery();
connection.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
`Inline Code Example Here`But it didn't work because of
System.FormatException: "Invalid input string format."
2) I've tried that UserAddedRow event too(which will be in code snippet).
but then have that exception in below:
System.NullReferenceException: The object reference has not been set to the instance of the object. System.Windows.Forms.DataGridViewCell.Value.get returned null.”
Then i tried removing 2 lines of code:
int id = (int)Convert.ToInt64(e.Row.Cells[0].Value.ToString()); cmd.Parameters.Add("@ID", MySqlDbType.Int64).Value = id;
And it didn't help.
Can someone please write how to solve it? I've searched something but i don't know how to deal with. Greetings.
private void dataGridView4_UserAddedRow(object sender, DataGridViewRowEventArgs e)
{
string name_project= e.Row.Cells[1].Value.ToString();
int id = (int)Convert.ToInt64(e.Row.Cells[0].Value.ToString());
MySqlConnection connection = new MySqlConnection("datasource = localhost; port = 3306; username = root; password = ");
MySqlCommand cmd = new MySqlCommand("INSERT INTO projekt1.projects(PROJECT_NAME) VALUES(@NPROJECT_NAME);", connection);
cmd.Parameters.Add("@ID", MySqlDbType.Int64).Value = id;
cmd.Parameters.Add("@PROJECT_NAME", MySqlDbType.VarChar).Value = name_project;
try
{
connection.Open();
cmd.ExecuteNonQuery();
connection.Close();
MessageBox.Show("ok");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}