CODEWITHSUNDEEP
c#ms-accessado.netoledb
user3043233
user3043233

Reputation:

How to fetch data from access database in a textBox using C#

I have a database in which I created a table HUGO_BOSS. Its columns are [brand name], [stock quantity], [retail price] and its primery key is [Brand name]. I want to fill my textbox in windows form with the value of stock quantity present in my database. I tried the following code but it gives run-time error

The Connection was not close, the connection state is open. 

if (comboBox2.Text == "HUGO BOSS")
{
    try
    {
        OleDbCommand cmd = con.CreateCommand();
        cmd.CommandText = "Select [Stock quantity] as stockquantity from HUGO_BOSS WHERE [Brand name]=@name";
        cmd.Parameters.AddWithValue("@name", comboBox3.SelectedItem);
        con.Open();
        OleDbDataReader dr = cmd.ExecuteReader(CommandBehavior.SingleResult);
        if (dr.Read())
        {
            textBox7.Text = dr["stockquantity"].ToString();
        }
    }
    finally { con.Close(); }
}

One more thing, here I will select the primary key by using a combobox3

Upvotes: 1

Views: 7674

Answers (1)

p.s.w.g
p.s.w.g

Reputation: 148980

It looks you're trying to reuse a database connection that is already open.

You could try testing the connection state before trying to open it:

OleDbCommand cmd = con.CreateCommand();
cmd.CommandText = "Select [Stock quantity] as stockquantity from HUGO_BOSS WHERE [Brand name]=@name";
cmd.Parameters.AddWithValue("@name", comboBox3.SelectedItem);
if (con.State == ConnectionState.Closed)
{
    con.Open();
}
OleDbDataReader dr = cmd.ExecuteReader(CommandBehavior.SingleResult);
if (dr.Read())
{
    textBox7.Text = dr["stockquantity"].ToString();
}

Alternatively, you could create a new connection each time you need to execute a new command.

Upvotes: 1

Related Questions