Question

    void Main()
    {
        string connString;
        connString = "Data Source=(local);Initial Catalog=Ochhi che guardano;Integrated Security=SSPI";


        String sqlString;
        try
        {
            SqlConnection conn = new SqlConnection(connString);
            conn.Open();
            sqlString = "SELECT Vare.varenavn";
            sqlString += " FROM vare";
            sqlString += " ORDER BY vare.varenavn";
            SqlCommand cmd = new SqlCommand(sqlString, conn);
            SqlDataReader reader =
            cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
            if (reader.HasRows)
            {
                reader.Read();
                Console.WriteLine(reader.GetString(0));
            }
            reader.Close();
            conn.Close();
        }
        catch (System.Data.SqlClient.SqlException e)
        {
            Console.WriteLine(e.ToString());
        }
    }
}

}

I have this database, where i have a list of goods i need printed to a text file and saved and the heard drive. (vare = goods). But when i run this code, i get an error. My question is what i am doing wrong with this code and how i can save the list in a .txt file. I know how files are handled in C#, but not how to integrate it with my database.

Answer 1

I suspect that you are getting multiple rows back, and currently you are able to display only a single row. That is because you are not iterating through the reader. Try the following in place of you your if block.

while (reader.Read())
{
    Console.WriteLine(reader.GetString(0));
}

If you want to store the data in a text file you can store each returned string in a list and then write that list to text file. So your code would be:

try
{
    SqlConnection conn = new SqlConnection(connString);
    conn.Open();
    sqlString = "SELECT Vare.varenavn";
    sqlString += " FROM vare";
    sqlString += " ORDER BY vare.varenavn";
    SqlCommand cmd = new SqlCommand(sqlString, conn);
    SqlDataReader reader =
    cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
    List<string> strList = new List<string>();
    while (reader.Read())
    {
        string temp = reader.GetString(0);
        strList.Add(temp);
        Console.WriteLine(reader.GetString(0));
    }
    reader.Close();
    conn.Close();
   //code to write list to text file
   File.WriteAllLines(Application.StartupPath + "\\text.txt", strList.ToArray());
}
catch (System.Data.SqlClient.SqlException e)
{
    Console.WriteLine(e.ToString());
}