asp.net中连接各种数据库字符串连接程序(mysql/mssql/access)

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Common;
using System.Linq;
using System.Text;
using System.Data.OleDb;
using System.Data.SqlClient;
using System.Data.Sql;

namespace ado
{
    public class ConnectionDemo1
    {
        public void GetOleDbTable()
        {
            #region namespace
            //using System.Data.OleDb;
            #endregion

            #region OLEDB Access

            //OLEDB
            //C#连接Access的方式

            //Access 2003   Provider=Microsoft.Jet.OLEDB.4.0
            //Access 2007   Provider=Microsoft.Ace.OleDb.12.0

            //(1)无数据库密码，无用户密码，共享方式打开
            //"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:qjx文档GenericDemoDataStudent.accdb;"
            //(2)有数据库密码，没有用户密码,这种方式以独占方式打开
            //"Provider=Microsoft.Jet.OleDB.4.0;Data Source=D:qjx文档GenericDemoDataStudent.accdb;Jet OleDb:DataBase Password=123"
            //(3)有数据库密码，有用户密码 可以用该方法,但用户密码处就算设有密码也必须为空，这种方式以独占方式打开
            //"Provider=Microsoft.Jet.OleDB.4.0;Data Source=D:qjx文档GenericDemoDataStudent.accdb;Jet OleDb:DataBase Password=12345;Persist Security Info=true;password=;user id=Admin"

            #endregion

            #region OLEDB MSSQL

            //OLEDB
            //C#连接MSSQL的方式

            //Windows 身份验证
            //"Provider=SQLOLEDB;Data Source=PEK7-6TKX23XSQLEXPRESS;Initial Catalog=Test;Trusted_Connection=Yes;";
            //SQL Server 身份验证
            //"Provider=SQLOLEDB;Data Source=127.0.0.1SQLEXPRESS;Initial Catalog=Test;User Id=sa;Password=123456;";

            #endregion

            #region OLEDB Oracle
            //OLEDB
            //C#连接Oracle的方式

            //"Provider=MSDAORA;Data Source=MyDatabaseAlias;User ID=MyUID;Password=MyPassword";
            #endregion

            //string strConn = @"Provider=Microsoft.Ace.OleDb.12.0;Data Source=D:qjx文档GenericDemoDataStudent.accdb;Jet OleDb:DataBase Password=123";//Access 2007
            string strConn =
                @"Provider=SQLOLEDB;Data Source=127.0.0.1SQLEXPRESS;Initial Catalog=Test;User Id=sa;Password=123456;";
            OleDbConnection conn = new OleDbConnection(strConn);
            OleDbCommand comm = new OleDbCommand();

            comm.CommandText = "SELECT * FROM Users";
            comm.CommandType = CommandType.Text;
            comm.Connection = conn;
            if (conn.State != ConnectionState.Open)
            {
                conn.Open();
                DataSet ds = new DataSet();
                OleDbDataAdapter da = new OleDbDataAdapter(comm);
                da.Fill(ds);
                conn.Close();
            }
        }

        public void GetSqlConnectionTable()
        {
            #region namespace
            //using System.Data.SqlClient;
            #endregion

            #region MSSQL SqlConnection
            //SqlConnection
            //C#连接MSSQL的方式

            //Windows 身份验证
            //"Data Source=PEK7-6TKX23XSQLEXPRESS;Initial Catalog=Test;Trusted_Connection=Yes;";
            //SQL Server 身份验证
            //"server=127.0.0.1SQLEXPRESS;database=Test;Uid=sa;PassWord=123456";
            #endregion

            //string strConn = @"server=127.0.0.1SQLEXPRESS;database=Test;Uid=sa;PassWord=123456";
            string strConn = @"Data Source=PEK7-6TKX23XSQLEXPRESS;Initial Catalog=Test;Trusted_Connection=Yes;";
           
            SqlConnection conn = new SqlConnection(strConn);
            SqlCommand comm = new SqlCommand();
            comm.CommandText = "SELECT * FROM Users";
            comm.CommandType = CommandType.Text;
            comm.Connection = conn;

            if(conn.State!=ConnectionState.Open)
            {
                conn.Open();
                DataSet ds = new DataSet();
                SqlDataAdapter da = new SqlDataAdapter(comm);
                da.Fill(ds);
                conn.Close();
            }

        }
    }
}

//OLEDB
//C#连接Access的方式

//Access 2003   Provider=Microsoft.Jet.OLEDB.4.0
//Access 2007   Provider=Microsoft.Ace.OleDb.12.0

//(1)无数据库密码，无用户密码，共享方式打开
//"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:qjx文档GenericDemoDataStudent.accdb;"
//(2)有数据库密码，没有用户密码,这种方式以独占方式打开
//"Provider=Microsoft.Jet.OleDB.4.0;Data Source=D:qjx文档GenericDemoDataStudent.accdb;Jet OleDb:DataBase Password=123"
//(3)有数据库密码，有用户密码 可以用该方法,但用户密码处就算设有密码也必须为空，这种方式以独占方式打开
//"Provider=Microsoft.Jet.OleDB.4.0;Data Source=D:qjx文档GenericDemoDataStudent.accdb;Jet OleDb:DataBase Password=12345;Persist Security Info=true;password=;user id=Admin"