连接池与数据库

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace 连接池
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnConnect_Click(object sender, EventArgs e)
        {

            //string connStr = @"server=.;database=MyDB;uid=sa;pwd=123;integrated security=true";
            //// string sql = "insert into Table_loginTest(uid,pwd)values('"+uid+"','"+pwd+"')";
            //// string sql = string.Format("insert into Table_loginTest(uid,pwd)values('{0}','{1}')", uid, pwd);
            //Stopwatch sp = new Stopwatch();
            //sp.Start();

            //for (int i = 0; i < 1000; i++)
            //{
            //    SqlConnection conn = new SqlConnection(connStr);
            //    conn.Open();
            //    conn.Close();
            //}
            //sp.Stop();
            //txtTime.Text = sp.Elapsed.ToString();

            string connStr = @"server=.;database=MyDB;uid=sa;pwd=123;integrated security=true;pooling=true";
            // string sql = "insert into Table_loginTest(uid,pwd)values('"+uid+"','"+pwd+"')";
            // string sql = string.Format("insert into Table_loginTest(uid,pwd)values('{0}','{1}')", uid, pwd);
            Stopwatch sp = new Stopwatch();
            sp.Start();

            for (int i = 0; i < 1000; i++)
            {
                SqlConnection conn = new SqlConnection(connStr);
                conn.Open();
                conn.Close();
            }
            sp.Stop();
            txtTime.Text = sp.Elapsed.ToString();
          


        }
    }
}

=>要点说明，

1.数据库连接池的开启跟关闭
当我们有多个对象，需要连接数据库的时候，这个时候会涉及到连接池，因为开启连接池，会提高连接速度。
具体的参见:
string connStr = @"server=.;database=MyDB;uid=sa;pwd=123;integrated security=true;pooling=true";
pooling=true 打开连接池</strong></span>
pooling=false 关闭连接池</strong></span>
注意：数据库的连接需要晚点打开，早点关闭
conn.Open();
conn.Close();

2.代码中，如何监视一段代码的执行时间
Stopwatch sp = new Stopwatch();
sp.Start();
。。。
sp.Stop();
 sp.Elapsed 就是所需的代码执行时间