How to store multiple user names in a variable?

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How to store multiple user names in a variable?

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#1 by (1 votes)
#2 by (0 votes)

1

I have a form , and I make a query in the database:

private void Consulta()
{
  var dataCom = Convert.ToDateTime(label1.Text).ToShortDateString(); 

  var conf = $"select * from data where data_venc = '{Datacom}'";
  var comando = new MySqlCommand(conf, conn);

  conn.Open();

  var retorno = Convert.ToInt32(comando.ExecuteScalar());

  conn.Close();
}

The variable Datacom receives the current system date.

In the database I have two dates (date of registration and expiration date), when making the user registration, I add 30 days and saved as the due date.

I want to check if the due date is the same as the system, if so, save the user names in a variable (or whatever the type) so that I can use it later.

After saving these names of these variables, I want to get each name to send emails each with their name.

How can I do this?

mysql c#

asked by anonymous 19.04.2017 / 05:41

2 answers

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score 1 · Answer 1

As your code is, it will not return the records in the database, only the total of affected records (% with%). To return the logs, and then go through them, you will have to use the command ExecuteScalar .

How do you want to store in a variable, just use it. I have modified your method to either be able to return the records of your query :

private MySqlDataReader Consulta(string connectionString) {
    MySqlDataReader retorno;

    using (var conn = new MySqlConnection(connectionString)) {


        var dataCom = Convert.ToDateTime(label1.Text).ToShortDateString();

        var conf = "select * from data where data_venc = @dataCom";
        conn.Open();

        using (var comando = new MySqlCommand(conf, conn)) {
            comando.Parameters.AddWithValue("@dataCom", dataCom);

            retorno = comando.ExecuteReader();
        }
    }
    return retorno;
}

With this method, you can then create a loop to go through the records, and with that, send the emails as you wish.

while (Consulta("sua_string_conexao").Read()) {
    //Percorre o datareader - cara interação será um usuario que poderá enviar o email

}