using System;
using System.Data.SqlClient;  //引入命名空間
namespace Csharpone
{
  class Program
  {
    static void Main(string[] args)
    {
      //windows 身份信息驗(yàn)證  下面的csharp01為新建的數(shù)據(jù)庫(kù)名稱(chēng)
      string constr = "Server.;integrated security=SSPI;Initial Catalog=csharp01";
      SqlConnection mysqlCon = new SqlConnection(constr); //實(shí)例化
      mysqlCon.Open(); //打開(kāi)數(shù)據(jù)庫(kù)
      Console.WriteLine("數(shù)據(jù)庫(kù)打開(kāi)");  //正常打印說(shuō)明沒(méi)問(wèn)題，否則會(huì)拋出異常
      //SQ驗(yàn)證方式 name是你設(shè)置的數(shù)據(jù)庫(kù)的用戶(hù)名，pwd是密碼 csharp02是數(shù)據(jù)庫(kù)名稱(chēng)
      string constr1 = "Server.;user=name; pwd=mima; database=csharp02";
      SqlConnection mysqlCon1 = new SqlConnection(constr1); //實(shí)例化
      mysqlCon1.Open(); //打開(kāi)數(shù)據(jù)庫(kù)
      Console.WriteLine("SQL方式 數(shù)據(jù)庫(kù)打開(kāi)");
 /*通過(guò)using語(yǔ)句實(shí)現(xiàn)數(shù)據(jù)庫(kù)的關(guān)閉
      using (mysqlCon1) {
        mysqlCon1.Open();
        Console.WriteLine("數(shù)據(jù)成功打開(kāi)");  //執(zhí)行完立即關(guān)閉
      }
      //通過(guò)try..catch..finally..
      try
      {
        mysqlCon.Open();
        Console.WriteLine("數(shù)據(jù)庫(kù)關(guān)閉");
      }
      catch
      {
      }
      finally
      {
        mysqlCon.Close();
        Console.WriteLine("關(guān)閉數(shù)據(jù)庫(kù)");
      }*/
//以上兩種方式結(jié)合使用，確保數(shù)據(jù)庫(kù)占用資源得到釋放
      try
      {
        using (mysqlCon)
        {
          mysqlCon.Open();
   Console.WriteLine("打開(kāi)數(shù)據(jù)庫(kù)");
        }
      }
      catch
      {
      }
      finally
      {
        mysqlCon.Close();
     Console.WriteLine("關(guān)閉數(shù)據(jù)庫(kù)");
      }
      Console.Read();
    }
  }
}

using System;
using MySql.Data.MySqlClient;  //導(dǎo)入引用，并且添加命名空間
namespace CSharp連接Mysql
{
  class Program
  {
    static void Main(string[] args)
    {
      string connectStr = "server=localhost;port=3306;database=czhenya01;user=root;password=123456;";
      //并沒(méi)有建立數(shù)據(jù)庫(kù)連接
      MySqlConnection conn = new MySqlConnection(connectStr);
      try
      {
        conn.Open();  //建立連接，打開(kāi)數(shù)據(jù)庫(kù)
        Console.WriteLine("打開(kāi)數(shù)據(jù)庫(kù)成功");
      }catch (Exception ex)
      {
        Console.WriteLine(ex.ToString());
      }
      finally
      {
        conn.Close();  //關(guān)閉連接
      }      
      Console.ReadKey();
    }
  }
}