c#操作的SQL-Server数据库以及dataReader与datagridview的捆绑

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以下是获取数据库数据的两种写法：

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

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

        private void button1_Click(object sender, EventArgs e)
        {
            ReadTable();
        }

        private void ReadTable()
        {
            string Constr = "Data Source=Windows身份验证;Initial Catalog=数据库名称;Trusted_Connection=true;";
            SqlConnection sqlCon = new SqlConnection(Constr);
            string sql = "SELECT * FROM [User]";//sql语句
            SqlDataReader reader = null;
            try
            {
                sqlCon.Open();
                // 捆绑方法之一，利用BindingSource
                SqlCommand cmd = new SqlCommand(sql, sqlCon);
                reader = cmd.ExecuteReader();//执行sql语句
                //BindingSource：封装窗体的数据源
               // BindingSource bs = new BindingSource();//捆绑源
                //DataSource:获取或设置连接绑定的数据源
                //bs.DataSource = reader; //捆绑执行结果
                //dataGridView1.DataSource = bs;
                //捆绑方法之二，利用datatable
                DataTable table = new DataTable();
                table.Load(reader);
                dataGridView1.DataSource = table;
            }
            catch (Exception)
            {
                MessageBox.Show("获取数据失败");
            }
            finally
            {
                reader.Close();
                sqlCon.Close();
            }
        }
    }
}