vs2015 连接mysql

//添加MySql.Data.dll 引用

using MySql.Data.MySqlClient;
using System;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        private static String mysqlcon = "Database=yundaclient;Password=abc@123456;User ID=root;server=127.0.0.1;charset=utf8";
        private MySqlConnection conn;
        private MySqlDataAdapter mDataAdapter;

        public Form1()
        {
            String sname = "Hello,Yummy!";
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            this.button1.Click += new System.EventHandler(this.ShowMessage);
            conn = new MySqlConnection(mysqlcon);
        }

        private void ShowMessage(object sender, EventArgs e)
        {
            MessageBox.Show("Hello,world!");
        }

        private void button1_Click(object sender, EventArgs e)
        {
            MessageBox.Show("Hello,world123456789!");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                conn = new MySqlConnection(mysqlcon);
                mDataAdapter = new MySqlDataAdapter("select * from admin", conn);
                mDataAdapter.Fill(dataSet1, "Yummy");
                dataGridView1.DataSource = dataSet1.Tables["Yummy"];
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            finally
            {
            }
        }

        private void chart1_Click(object sender, EventArgs e)
        {
        }
    }
}