I can't get my static class working with a Generic List - asp.net

Question

I have a static class that needs to pass a generic List of strings to a function using an integer as a index to the List in the class. The problem is the static class doesn't have a List collect and I don't have a proper index to access the class in the function it is passed to. The class, the calling code, and the receiving function are below.
My Class:
public class QueryContainer
{
public static QueryContainer Instance = new QueryContainer();
private int _id;
private string _query = "";
private int _searchID;
public QueryContainer() { }
public string Query
{
get
{
if (Instance != null)
return Instance._query;
else
return "";
}
set { _query = value; _id =+ 1; }
}
public int ID { get { return _id; } }
public int SearchID
{
set { _searchID = value; }
get { return _searchID; }
}
}
The calling code:
public int GetAccountSortByAccountCode(int account)
{
int Id = 0;
QueryContainer.Instance.Query = "SELECT ac_sort_order FROM lkup_account_codes where ac_code = " + account.ToString();
return Convert.ToInt32(ExecuteScaler(Id));
}
The function that the static class is passed to:
public int GetAccountSortByAccountCode(int account)
{
int Id = 0;
QueryContainer.Instance.Query = "SELECT ac_sort_order FROM lkup_account_codes where ac_code = " + account.ToString();
return Convert.ToInt32(ExecuteScaler(Id));
}
The Function
protected Object ExecuteScaler(int ID)
{
object returnValue = null;
if (!_iserror)
{
if (_trace)
{ DoTrace("TAMIS.Data.Loader.ExecuteScalar", QueryContainer.Instance.Query); }
if (_connection == null || _connection.State == ConnectionState.Closed)
{
OpenConnection();
}
DbCommand command = _provider.CreateCommand();
command.Connection = _connection;
{
command.CommandText = QueryContainer.Instance.Query;
command.CommandType = CommandType.Text;
if (_useTransaction) { command.Transaction = _transaction; }
try
{
returnValue = command.ExecuteScalar();
}
catch (Exception ex)
{
if (ex is EntryPointNotFoundException)
throw ex;
//if (_useTransaction == true)
//_transaction.Rollback();
RollBack();
LogBLL bll = new LogBLL();
bll.WriteErrorLog(ex);
_iserror = true;
}
finally
{
if ((!KeepAlive && _connection.State == ConnectionState.Open) || _iserror == true)
{
CloseConnection();
}
}
}
}
else
{
returnValue = -1;
}
return returnValue;
}

Answer 1

You are using QueryContainer as a Singleton.
In ASP.Net, you receives multiple requests from different users. It is not a good way to construct dynamic query.
Basically, what you are doing is all requests will use same QueryContainer instance. I don't think it is what you want.
The bottom line is do not use static in your scenario.