EF学习记录

 

 

1.四种模型区别

 

 

1.Database First学习链接：

https://www.cnblogs.com/1175429393wljblog/p/10775763.html

2.Model First学习链接：

http://www.10qianwan.com/articledetail/42545.html

https://www.cnblogs.com/1175429393wljblog/p/10775251.html

3.Code First学习链接：

https://www.cnblogs.com/alunchen/p/6903753.html

 控制台命令输入

 

 增删改查：

 //增
        private void button1_Click(object sender, EventArgs e)
        {
            using (MyModel mymodel = new MyModel())
            {
                mymodel.Schools.Add(new School() { Key = 2, Name = "画川中心", Uid = 1 });
                mymodel.SaveChanges();
            }
        }
        //查

        private void button2_Click(object sender, EventArgs e)
        {
            using (MyModel mymodel = new MyModel())
            {
                dataGridView1.DataSource = mymodel.Schools.ToList();
            }
        }
        //删
        private void button4_Click(object sender, EventArgs e)
        {
            using (MyModel mymodel = new MyModel())
            {
                mymodel.Schools.Remove(mymodel.Schools.FirstOrDefault(x => (x.Key==1)));
                mymodel.SaveChanges();
            }
        }
        //改
        private void button3_Click(object sender, EventArgs e)
        {
            using (MyModel mymodel = new MyModel())
            {
               var model= mymodel.Schools.Where(x => (x.Key == 1)).FirstOrDefault();
                model.Name = "宝应中学";
                mymodel.SaveChanges();
            }
        }