ASP.NET

if(variable == null) {
  variable =  String.Empty; // provided variable is string type
}

<%# IIf(IsDBNull(DataBinder.Eval(Container.DataItem, "IsReferralRequired")) OrElse String.IsNullOrEmpty(DataBinder.Eval(Container.DataItem, "IsReferralRequired")) OrElse (Convert.ToBoolean(Eval("IsReferralRequired")) = False), "No", "Yes")%>

public static Type GetClrType(SqlDbType sqlType)
{
    switch (sqlType)
    {
        case SqlDbType.BigInt:
            return typeof(long?);

        case SqlDbType.Binary:
        case SqlDbType.Image:
        case SqlDbType.Timestamp:
        case SqlDbType.VarBinary:
            return typeof(byte[]);

        case SqlDbType.Bit:
            return typeof(bool?);

        case SqlDbType.Char:
        case SqlDbType.NChar:
        case SqlDbType.NText:
        case SqlDbType.NVarChar:
        case SqlDbType.Text:
        case SqlDbType.VarChar:
        case SqlDbType.Xml:
            return typeof(string);

        case SqlDbType.DateTime:
        case SqlDbType.SmallDateTime:
        case SqlDbType.Date:
        case SqlDbType.Time:
        case SqlDbType.DateTime2:
            return typeof(DateTime?);

        case SqlDbType.Decimal:
        case SqlDbType.Money:
        case SqlDbType.SmallMoney:
            return typeof(decimal?);

        case SqlDbType.Float:
            return typeof(double?);

        case SqlDbType.Int:
            return typeof(int?);

        case SqlDbType.Real:
            return typeof(float?);

        case SqlDbType.UniqueIdentifier:
            return typeof(Guid?);

        case SqlDbType.SmallInt:
            return typeof(short?);

        case SqlDbType.TinyInt:
            return typeof(byte?);

        case SqlDbType.Variant:
        case SqlDbType.Udt:
            return typeof(object);

        case SqlDbType.Structured:
            return typeof(DataTable);

        case SqlDbType.DateTimeOffset:
            return typeof(DateTimeOffset?);

        default:
            throw new ArgumentOutOfRangeException("sqlType");
    }
}<pre>

public int GetAccountSortByAccountCode(int account)
{
    using (var connection = new SqlConnection("YOUR CONNECTION STRING"))
    using (var command = new SqlCommand("SELECT ac_sort_order FROM lkup_account_codes where ac_code = @account", connection))
    {
        command.Parameters.AddWithValue("@account", account);

        connection.Open();
        return Convert.ToInt32(command.ExecuteScalar());
    }
}