How to solve the connection problem in the datagridview c#

ma ouml

9y900

Hi friends

I find this error

in this code but I do not know is what I will add con.open () and con .close () to the code

Program.cmd.CommandText = "select utilisateur.User_name,site.Libelle_site,profil.Libelle_profil from utilisateur,site,profil,autorisation where utilisateur.Id_user=autorisation.Id_user and site.Id_site=autorisation.Id_site and profil.Id_profil=autorisation.Id_profil";

Program.dr = Program.cmd.ExecuteReader();

DataTable dt = new DataTable();

dt.Load(Program.dr);

dataGridView1.DataSource = dt;

dataGridView1.Refresh();

8 Replies

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Bharathi Raja8y ago
your connection.close(); first closed and then connectio.open();
0
ma ouml9y ago
Rafnas T P

thank you
0
Rafnas T P9y ago
other wise you can check the is connection is open or closed then you can open.
as below
Program.cmd.CommandText = "select utilisateur.User_name,site.Libelle_site,profil.Libelle_profil from utilisateur,site,profil,autorisation where utilisateur.Id_user=autorisation.Id_user and site.Id_site=autorisation.Id_site and profil.Id_profil=autorisation.Id_profil";
if (con!= null && con.State == ConnectionState.Closed)
{
con.Open();//asuming your connection string is con
}
Program.dr = Program.cmd.ExecuteReader();
DataTable dt = new DataTable();
dt.Load(Program.dr);
dataGridView1.DataSource = dt;
dataGridView1.Refresh();
con.Close();
0
Rafnas T P9y ago
error says you have open the connection some where in yor code before calling this code,
so you have to close the connection before opening the connection,
so pls check your code properly, any where you open the connection close it as i Did
0
ma ouml9y ago
Rafnas T P
I did what you told me but it shows me the error that I have to close the connection even if I set con.open (); in the beginning
And con.close (); at the end

0
Rafnas T P9y ago
Try as below

Program.cmd.CommandText = "select utilisateur.User_name,site.Libelle_site,profil.Libelle_profil from utilisateur,site,profil,autorisation where utilisateur.Id_user=autorisation.Id_user and site.Id_site=autorisation.Id_site and profil.Id_profil=autorisation.Id_profil";
con.Open();//asuming your connection string is con
Program.dr = Program.cmd.ExecuteReader();
DataTable dt = new DataTable();
dt.Load(Program.dr);
dataGridView1.DataSource = dt;
dataGridView1.Refresh();
con.Close();
0
Rafnas T P9y ago
before executing
Program.dr = Program.cmd.ExecuteReader();
this code you need to open your conection,
so please add
con.Open();
before
Program.dr = Program.cmd.ExecuteReader();

and close your connection after done

con.Close(); (Note: Assuming con is your connection string)
0
Nilesh Shah9y ago
Is this your complete code?

I dont see anything related to connection object.

either copy-paste your complete code here or attach your .cs file as zip file

it seems to me your code is not complete
0

How to solve the connection problem in the datagridview c#

Rafnas T P

Rafnas T P