Query on Mysql database with asp.net core - mysql

Question

I need to query the database.
This query is working correctly, but I need to loop to read all data in the table.
I don't know how to put "do" or "while" in this query
[HttpPost]
public IActionResult SendMessage(string send_to, string message, string phone)
{
var email = HttpContext.Session.GetString("email");
MySqlDataReader reader;
try
{
cmdMySQL.Connection = conMySQL;
conMySQL.Open();
cmdMySQL.CommandText = "SELECT * FROM tbl_mensagens WHERE enviado = '" + 0 + "' AND email_usuario = '" + email + "' ";
reader = cmdMySQL.ExecuteReader();
while (reader.Read())
{
var codmsgx ="";
phone = "";
message = "";
codmsgx = reader[0].ToString();
phone = reader[4].ToString();
message = reader[5].ToString();
EnviarMensagem(send_to, message, phone, email, codmsgx);
AtualizarBd(send_to, message, phone, email, codmsgx);
}
reader.Close();
return View();
}
catch (Exception ex) { Debug.WriteLine(ex); return View(); }
finally
{
conMySQL.Close();
}
}

Answer 1

You're only getting one row because you're calling reader.Read(). Each time you call Read(), the reader advances to the next row and returns true; or, when the reader advances past the last row, it returns false.
Assume that you have a view model:
public class MensagensViewModel
{
public string Codmsgx { get; set; }
public string Phone { get; set; }
public string Message { get; set; }
}
To get the List<MensagensViewModel> data from tbl_mensagens table, you need to manually save the accessed data into mensagens shown as below code:
try
{
cmdMySQL.Connection = conMySQL;
cmdMySQL.CommandText = "SELECT * FROM tbl_mensagens WHERE enviado = '" + 0 + "' AND email_usuario = '" + email + "' ";
conMySQL.Open();
reader = cmdMySQL.ExecuteReader();
List<MensagensViewModel> mensagens = new List<MensagensViewModel>();//To save all retrieved data
while (reader.Read())
{
var mensagen = new MensagensViewModel()
{
Codmsgx = reader[0].ToString(),
Phone = reader[4].ToString(),
Message = reader[5].ToString()
};
mensagens.Add(mensagen);
//other logic
}
reader.Close();
return View();
}
catch (Exception ex) { Debug.WriteLine(ex); return View(); }
finally
{
conMySQL.Close();
}