Reading with MySqlDataReader

问题

Hello I'm having problem to read with MySqlDataReader. I've tried to change while() to if() and it worked then. So I'm doing something wrong with while (Reader.Read()). Thanks for answer. ( The other question today is fixed, someone that commented helped me xd )

using (MySqlCommand cmd = new MySqlCommand
      ("SELECT * FROM `citationer`",  mysqlCon))
{
    try
    {
        MySqlDataReader Reader = cmd.ExecuteReader();
        while (Reader.Read()) // this part is wrong somehow
        {
            citationstexter.Add(Reader.GetString(loopReading)); // this works
            loopReading++; // this works
        }
        Reader.Close();
    }

    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}

回答1:

Your problem is the use of the loopReading parameter to GetString. This parameter should be the zero-based column ordinal (the column number), but you're incrementing it for every row you read.

See here for more info: http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldatareader.getstring.aspx

You should use 0 for the first column of your citationer table, 1 for the second column, etc.

Also, it's good practice to use

  using(MySqlDataReader Reader = cmd.ExecuteReader()) 
  {
    ...
  }

just like you did for the mySqlCommand object to save a memory leak (but this is not your problem.)

来源：https://stackoverflow.com/questions/5606643/reading-with-mysqldatareader