EF方式增、删、改、查(基本使用)

  右击项目——添加——新建项——数据（C#）——选择ADO.NET实体数据模型——点击添加——然后根据实体数据模型向导来一步步的做。

用到的表

using System;
using System.Data;
using System.Linq;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void simpleButton1_Click(object sender, EventArgs e)
        {
            XtraForm1 xtraForm1 = new XtraForm1();
            xtraForm1.ShowDialog();
        }
        //查询
        private void simpleButton2_Click(object sender, EventArgs e)
        {
            using (NorthwindEntities db = new NorthwindEntities())
            {
                var cust = from c in db.Region select c;
                gridControl1.DataSource = cust.ToList();
            }
        }
        //增加
        private void simpleButton1_Click_1(object sender, EventArgs e)
        {
            using (NorthwindEntities db = new NorthwindEntities())
            {
                Region region = new Region();
                region.RegionID =int.Parse(textEdit1.Text.Trim());
                region.RegionDescription = textEdit2.Text.Trim();
                db.Region.Add(region);
                int rows = db.SaveChanges();
                MessageBox.Show(rows.ToString());
            }
        }
        //修改
        private void simpleButton3_Click(object sender, EventArgs e)
        {
            using (NorthwindEntities db = new NorthwindEntities())
            {
                int id = Convert.ToInt32(textEdit1.Text);
                Region region = db.Region.Where(i => i.RegionID == id).FirstOrDefault();
                if (region != null)
                {
                    region.RegionDescription = textEdit2.Text;
                    int rows = db.SaveChanges();
                    MessageBox.Show(rows.ToString());
                }
            }
        }
        //删除
        private void simpleButton4_Click(object sender, EventArgs e)
        {
            using (NorthwindEntities db = new NorthwindEntities())
            {
                int id = Convert.ToInt32(textEdit1.Text);
                Region region = db.Region.Where(i => i.RegionID == id).FirstOrDefault();
                if (region != null)
                {
                    db.Region.Remove(region);
                    int rows = db.SaveChanges();
                    MessageBox.Show(rows.ToString());
                }
            }
        }
        //单元格取值
        private void gridView1_RowCellClick(object sender, DevExpress.XtraGrid.Views.Grid.RowCellClickEventArgs e)
        {
            var index = gridView1.GetFocusedDataSourceRowIndex();
            textEdit1.Text = gridView1.GetRowCellValue(index, "RegionID").ToString().Trim();
            textEdit2.Text = gridView1.GetRowCellValue(index, "RegionDescription").ToString().Trim();
        }
    }
}

补充：批量增加数据

        //批量增加数据
        public void AddRange()
        {
            using (Northwind db = new Northwind())
            {
                List<Region> regions = new List<Region>();
                regions.Add(new Region { RegionID = 6, RegionDescription = "济南" });
                regions.Add(new Region { RegionID = 7, RegionDescription = "合肥" });
                regions.Add(new Region { RegionID = 8, RegionDescription = "天津" });
                db.Region.AddRange(regions);
                Response.Write(db.SaveChanges());
            }
        }

界面