C#-工廠模式獲得資料庫連線
using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Configuration;
using System.Data.Common;
namespace ConsoleApp2
{
class Program
{
static void Main(string[] args)
{
SqlConnection conn = null;
try
{
conn = (SqlConnection)GetConnection();
conn.Open();
Console.WriteLine("Open");
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
finally
{
conn.Close();
}
Console.Read();
}
private static DbConnection GetConnection()
{
ConnectionStringSettings conSetting = ConfigurationManager.ConnectionStrings["Northwind"];
DbProviderFactory factory = DbProviderFactories.GetFactory(conSetting.ProviderName);
DbConnection con = factory.CreateConnection();
con.ConnectionString = conSetting.ConnectionString;
return con;
}
}
}
/*********************App.config******************/
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1" />
</startup>
<connectionStrings>
<add name="Northwind" connectionString="server=.;database=D:\DATABASE\NORTHWND.MDF;uid=sa;pwd=Server2012;"
providerName="System.Data.SqlClient"/>
</connectionStrings>
</configuration>