Is there any proper way to retrieve data from OLEDB connection searched by some specific string value?

Question

I wanted to retrieve a Category from SQL Server using this query. I have data in the database and this query worked well in SQL Server. But when I use it with oledb command, it does not return any data from the server. What's the problem?

public Category GetCategoryByCategoryName(string categoryName)
{
    Category _category = null;

    using (OleDbConnection con = new OleDbConnection(_connectionString))
    {
        string sql = "select * from Categories where CategoryName=?";

        OleDbCommand cmd = new OleDbCommand(sql, con);
        cmd.Parameters.AddWithValue("@cName", categoryName);

        try
        {
            con.Open();
            OleDbDataReader rdr = cmd.ExecuteReader();

            if (rdr.HasRows)
            {
                while (rdr.Read())
                {
                    _category.Id = Convert.ToInt32(rdr["Id"]);
                    _category.CategoryName = rdr["CategoryName"].ToString();
                }

                rdr.Close();
            }
        }
        catch (Exception ex)
        {
            _category = null;
        }
    }

    return _category;
}

Answer 1

It should: Category _category = new Category(); instead of: Category _category = null;

Answer 2

I don't know about "proper" but a "good" way might be to install Dapper and reduce your code to:

    public Category GetCategoryByCategoryName(string categoryName)
    {
        using (OleDbConnection con = new OleDbConnection(_connectionString))
        {
            return con.QueryFirstOrDefault<Category>(
              "select * from Categories where CategoryName=?cn?",
              new { cn = categoryName }
            );
        }
    }

References: Passing query parameters in Dapper using OleDb