Saturday, October 19, 2013

MySQL Certification Study: Write a basic .NET application that uses MySQL

I've registered for the MySQL 5.6 beta exams, just like many more on Planet MySQL have done.

One of the topics for the MySQL 5.6 Developer exam is: "Write a basic .NET application that uses MySQL".

I have used Connector/Net a few times the last few years, but the last time I looked at some code involving Connector/Net was when I took the MySQL 5 Developer exam, which was long ago.

I'm using Linux on both my laptop and on servers for most projects. So I don't use or see many .NET code.

So I need a short refresh.

To use Connector/Net on Linux you will need to install Mono. The base for .NET is CIL, which exists in at least 4 versions: 1.0, 2.0 and 4.0. To compile C# code with mono you need the command which correspondends with the CIL version you are using.
  • CIL 1.0: mcs
  • CIL 2.0: gmcs
  • CIL 4.0: dmcs
For Ubuntu you'll need these packages:
  • libmono-system-data4.0-cil
  • libmysql-cil-dev
  • mono-runtime
  • mono-dmcs
  • pkg-config
So now we should be able to comple some C# code:
dmcs -r:System.Data.dll $(pkg-config --libs mysql-connector-net) example1.cs


And run it:
mono example1.exe


The Connector/Net Tutorial Intro on mysql.com has some example code.

I wrote some very very basic C# code based on the tutorial:
$ mono example1.exe
Connecting to MySQL...
5.6.12-log
Done.


The code:
using System;
using System.Data;

using MySql.Data;
using MySql.Data.MySqlClient;

public class Example1
{
 public static void Main(string[] args)
 {
  string connStr = "server=localhost;user=msandbox;database=test;port=5612;password=msandbox";
  MySqlConnection conn = new MySqlConnection(connStr);
  try
  {
   Console.WriteLine("Connecting to MySQL...");
   conn.Open();

   string sql = "SELECT VERSION()";
   MySqlCommand cmd = new MySqlCommand(sql, conn);
   MySqlDataReader rdr = cmd.ExecuteReader();

   while (rdr.Read())
   {
    Console.WriteLine(rdr[0]);
   }
  }
  catch (Exception ex)
  {
   Console.WriteLine(ex.ToString());
  }
  conn.Close();
  Console.WriteLine("Done.");
 }
}

2 comments:

  1. Hello, i need help with a conection a mysql in other pc, ever in vb.net

    ReplyDelete
  2. Please post your question to the MySQL Forums on http://forums.mysql.com/list.php?38 There is probably someone there who can assist you in setting up the MySQL connection. Please try to add as much details (setup, error messages, steps taken) as possible to your question.

    ReplyDelete