I am trying to figure out how to check if my SqlDataReader
is null or has no rows (meaning the reservation does not exist) and then display a messagebox. For some reason when I debug once it hits the While dr.Read())
code it steps out if it does not have a return result.
I've tried putting this code in a few different locations but none seem to fire off the messagebox if no records are returned
if (dr.GetValue(0) == DBNull.Value || !dr.HasRows)
{
MessageBox.Show("Reservation Number Does Not Exist","Error", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
}
else
{
(read records)
}
My code...
try
{
using (SqlConnection con = new SqlConnection(connectionString))
{
using (SqlCommand cmd = con.CreateCommand())
{
con.Open();
cmd.CommandText = "usp_StoredProcedureName";
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@regnum", regnumber);
using (SqlDataReader dr = cmd.ExecuteReader())
{
//Loop through all the rows, retrieving the columns you need.
while (dr.Read())
{
lblConf.Text = dr.GetValue(0).ToString();
lblName.Text = dr.GetValue(1).ToString() + "," + dr.GetValue(2);
lblCompany.Text = dr.GetValue(3).ToString();
lblStatus.Text = dr.GetValue(4).ToString();
}
}
}
}
}
catch (Exception ex)
{
MessageBox.Show("Can not open connection! ");
}
if(dr.HasRows)
{
// ....
}
else
{
MessageBox.Show("Reservation Number Does Not Exist","Error", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
}