Problem with my save dialog logic

Hi,

The code that you see its help to remove (ou delete) one column. Its works fine.

But the problem is I need to put a condition save logic. Its should show a dialog that allow if or not possible to save. Its show this dialog message but when I click yes its display this message error: Additional information: object reference not defined for instance object

private void btnDelete_Click(object sender, EventArgs e)
{
if (conn.State != ConnectionState.Open)
conn.Open();
OleDbCommand cmd = new OleDbCommand();
comm.Connection = conn;
if (MessageBox.Show("Are you sure to save?", "Save window", MessageBoxButtons.YesNo) == DialogResult.Yes)
{
try
{
cmd = new OleDbCommand("ALTER TABLE Billing DROP COLUMN ID ", conn);
comm.ExecuteNonQuery();
}
Finally
{
conn.Close();
}
}
}

1 Reply

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Jayakumar Balasubramaniam8y ago
Hi, I think you must have got this error before displaying Message itself i wonder how it passes. Okay, the issue is in comm.ExecuteNonquery() there is no object declared as "comm" that's why you get object reference error please change it as cmd.ExecuteNonquery() it will work