title: ASP.NET : the connection is closed
body: <p>I want to execute a query but we are facing the problem of connection string</p>
  
  <p>This is my code:</p>
  
  <pre><code>OracleCommand _commandInvoice = new OracleCommand();
  _commandInvoice.CommandType = CommandType.StoredProcedure;
  
  _commandInvoice.Parameters.AddWithValue("I_INVOICE_ID", strInvoiceID);
  _commandInvoice.Parameters.AddWithValue("I_ORG_ID", ORG_ID);
  _commandInvoice.Parameters.AddWithValue("I_ORG_NAME", strOrg_name);
  _commandInvoice.Parameters.AddWithValue("I_PROJECT", strProject);
  _commandInvoice.Parameters.AddWithValue("I_VENDOR_NAME", strVendor_name);
  _commandInvoice.Parameters.AddWithValue("I_VENDOR_TYPE_LOOKUP_CODE", strVendorType_lookup_Code);
  _commandInvoice.Parameters.AddWithValue("I_INVOICE_NUMBER", strInvoice_number);
  _commandInvoice.Parameters.AddWithValue("I_INVOICE_DATE", strInvoice_date);
  _commandInvoice.Parameters.AddWithValue("I_INVOICE_AMT", strInvoice_Amt);
  _commandInvoice.Parameters.AddWithValue("I_OUTSTANDING_AMT", strOutstanding_Amt);
  _commandInvoice.Parameters.AddWithValue("I_OUTSTANDING_REQ_AMT", strOutstanding_req_amt);
  
  if (obj_Conn.State == ConnectionState.Closed)
  {
      obj_Conn.Open();
      _commandInvoice.ExecuteNonQuery();
  }
  </code></pre>
  
  <p>We are getting am error:</p>
  
  <blockquote>
    <p>Invalid operation. The connection is closed.</p>
  </blockquote>