C#连接SQL Server数据库的四种方式

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;

namespace ADONET
{
class Program
{
static void Main(string[] args)
{
//【1】windows认证模式：
// String strCon = "Data Source=localhost;Initial Catalog=SIMS;Integrated Security=true";

//【2】SQLSERVER认证模式：
//String strCon = "Data Source=.;Initial Catalog=SIMS;User Id=sa;Password=";

//【3】通过工具生成连接字符串
//String strCon = "Data Source=穆岭-PC;Initial Catalog=SIMS;Persist Security Info=True;User ID=sa Password=";

//【4】通过连接字符串生成器生成
SqlConnectionStringBuilder scsb = new SqlConnectionStringBuilder();
scsb.DataSource = ".";
scsb.InitialCatalog = "SIMS";
scsb.UserID = "sa";
scsb.Password = "";
String strCon = scsb.ConnectionString;  //得到连接字符串

SqlConnection con = null;
SqlCommand com = null;
SqlDataReader sdr = null;
try
{
con = new SqlConnection(strCon);
com = con.CreateCommand();
com.CommandText = "SELECT cname FROM Course";
con.Open();
sdr = com.ExecuteReader();
while (sdr.Read())
{
Console.WriteLine(sdr[0]);
}
}catch(Exception e){
Console.WriteLine(e.Message);
}finally{
sdr.Close();
com.Clone();
con.Close();
}
Console.ReadKey();
}
}
}