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Local variable not assigned in while loop

Jim Riddles
Jim Riddles asked
Last Modified: 2020-03-10
I am creating a program that will generate X number of codes that must not already exist in a MySQL table.I am trying to read all of the codes in the current table, and store it within an array.  However, I can't seem to get that to work, either.  Below is the code that I have, but I get an error within the while block indicating that ExistingCodes has not been initialized, which puzzles me.  Use of unassigned local variable 'ExistingCodes' is the precise error.  What am I doing wrong here?  Is there a better way of doing this?  Keep in mind that I am going to use this array to check against when generating the new codes, and adding the new codes as they are generated.

    public static string[] GetExistingCodes
        int index = 0;
        string[] ExistingCodes;
        string sql = "SELECT code from `gift_codes`";
        MySqlCommand cmd = new MySqlCommand(sql, Conn);
        MySqlDataReader rdr = cmd.ExecuteReader();
        while (rdr.HasRows)
          ExistingCodes[index] = rdr.GetString(0);
        return ExistingCodes;

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